Embryogenesis of tubes. The fallopian tubes are derivatives of the Müllerian ducts. It is known that in an embryo about 8 mm long, the development of the Müllerian ducts in the form of a groove on the outer surface of the primary kidney is already planned. Somewhat later, the groove deepens to form a channel, the upper (head) end of which remains open, and the lower (tail) end ends blindly. Gradually, the tail paired sections of the Müllerian ducts grow downward, and they approach the medial (middle) section of the embryo, where they merge with each other. The uterus and upper vagina are subsequently formed from the fused Müllerian ducts. Thus, when the Müllerian canals grow, they first have a vertical and then a horizontal direction. The place where the direction of their growth changes corresponds to the place where the fallopian tubes depart from the uterus.
The head ends of the Müllerian canals form the fallopian tubes with an opening - the abdominal openings of the tubes, around which epithelial outgrowths - future fimbriae - develop. Often, with the main opening (funnel), several side openings are formed, which either disappear or remain in the form of additional openings of the fallopian tubes.
The lumen of the tube is formed by melting the centrally located sections of the Müllerian canal. Starting from the 12th week of embryonic development, longitudinal folds are formed at the abdominal end of the tubes, which gradually move along the entire tube and by the 20th week reach the uterine end (N. M. Kakushkin, 1926; K. P. Ulezko-Stroganova, 1939) . These folds, being primary, gradually increase, giving additional outgrowths and lacunae, which determines the complex folding of the pipe. By the time a girl is born, the epithelial lining of the fallopian tubes forms cilia.
The growth of the tubes in the embryonic period, with the simultaneous descent of the ovary into the pelvic cavity, leads to spatial convergence of the uterus and tubes (the abdominal and uterine sections of the tubes are on the same horizontal line). This convergence causes the formation of tortuosity, which gradually disappears. By the time a girl is born, tortuosity is detected only in the area of the abdominal openings; by the onset of puberty, it completely disappears (Fig. 1). The wall of the tube is formed from mesenchyme, and by the 20th week of intrauterine development all muscle layers are well defined. The mesenchymal part of the Wolffian bodies and the epithelium of the abdominal cavity (peritoneum) form the broad ligament of the uterus and the outer (serous) covering of the tube.
Congenital absence of both fallopian tubes occurs in nonviable fetuses with developmental anomalies of other organs.
Although the tubes and uterus are derivatives of the Müllerian canals, i.e., they have the same embryonic source, with aplasia of the uterus the tubes are always well developed. A congenital pathology may occur when a woman is missing one ovary, has aplasia of the uterus and vagina, but the structure of the tubes is normal. Perhaps this is due to the fact that the tubes develop into a full-fledged formation at earlier stages of embryogenesis than the uterus and vagina, and if they do not develop, the factors that caused this pathology simultaneously act on other foci of organogenesis, which leads to the appearance of deformities, incompatible with life.
At the same time, it has been proven that with anomalies of the uterus and vagina, the embryonic development of vital organs and the central nervous system is basically completed, so it is not so rare to find women with anomalies of the uterus and vagina with normal tubes.
Normal tubal anatomy. Starting in the corners of the uterus, the fallopian tube (tuba uterina s. salpinx) penetrates the thickness of the myometrium almost in a strictly horizontal direction, then deviates slightly backward and upward and is directed as part of the upper part of the broad ligament to the lateral walls of the pelvis, bending around the ovary along the way. On average, the length of each pipe is 10-12 cm, less often 13-16 cm.
There are four parts in the pipe [show] .
Parts of the fallopian tube
- interstitial (interstitial, intramural, pars tubae interstitialis), about 1 cm long, located in the thickness of the uterine wall, has the narrowest lumen (about 1 mm),
- isthmic (isthmic, isthmus tubae), about 4-5 cm long and 2-4 mm in lumen,
- ampullary (ampula tubae), 6-7 cm long and with a lumen gradually increasing in diameter to 8-12 mm as it moves in the lateral direction,
- The abdominal end of the tube, also called the funnel (infundibulum tubae), is a short extension that opens into the abdominal cavity. The funnel has several epithelial outgrowths (fimbria, fimbria tubae), one of which is sometimes 2-3 cm long, often located along the outer edge of the ovary, fixed to it and called ovarian (fimbria ovarica)
The wall of the fallopian tube consists of four layers [show] .
Layers of the wall of the fallopian tube
- The outer, or serous, membrane (tunica serosa) is formed from the upper edge of the broad uterine ligament, covers the tube on all sides, with the exception of the lower edge, which is free from the peritoneal cover, since here the duplication of the peritoneum of the broad ligament forms the mesentery of the tube (mesosalpinx).
- Subserosal tissue (tela subserosa) is a loose connective tissue membrane, weakly expressed only in the area of the isthmus and ampulla; on the uterine part and in the area of the funnel of the tube, subserosal tissue is practically absent.
- The muscular layer (tunica muscularis) consists of three layers of smooth muscle: a very thin outer layer - longitudinal, a larger middle layer - circular and inner layer - longitudinal. All three layers are closely intertwined and directly pass into the corresponding layers of the myometrium. In the interstitial part of the tube, condensation of muscle fibers is detected mainly due to the circular layer with the formation of the sphincter tubae uterinae. It should also be noted that as we move from the uterus to the abdominal end, the number of muscle structures in the tubes decreases until they are almost completely absent in the funnel area of the tube, where muscle formations are determined in the form of separate bundles.
- The mucous membrane (tunica mucosa, endosalpinx) forms four longitudinal folds along the entire length of the tube, between which there are secondary and tertiary smaller folds. This results in the pipe having a scalloped shape when cut. There are especially many folds in the ampullary section and in the funnel of the tube.
The inner surface of the fimbriae is lined with mucous membrane, the outer surface is lined with abdominal mesothelium, which passes into the serous membrane of the tube.
Histological structure of the tube.
- The serous membrane consists of a connective tissue base and mesodermal epithelial cover. In the connective tissue base there are bundles of collagen fibers and fibers of the longitudinal layer of muscle.
Some researchers (V.A. Bukhshtab, 1896) found elastic fibers in the serous, subserous and muscle layers, while K.P. Ulezko-Stroganova (1939) denied their presence, with the exception of the walls of the tube vessels.
- The mucous membrane includes a stroma, consisting of a network of thin collagen fibers with spindle-shaped and process cells, and there are vagus and mast cells. The epithelium of the mucous membrane is high cylindrical with ciliated cilia. The closer the section of the tube is located to the uterine angles, the shorter the length of the cilia and the height of the epithelium (R. N. Bubes, 1949).
Studies by N.V. Yastrebov (1881) and A.A. Zavarzin (1938) showed that the mucous membrane of the tubes does not have glands; the secretory elements are epithelial cells, which swell at the moment of secretion, and after being released from the secretion they become narrow and elongated.
S. B. Edelman-Reznik (1952) distinguishes several types of fallopian tube epithelium: 1) ciliated, 2) secretory, 3) basal, 4) cambial, considering the latter type to be the main producer of the remaining cells. Studying the features of the tubal epithelium in tissue culture, Sh. D. Galsgyan (1936) found that it is strictly determined.
The question of the cyclic transformations of the endosalpinx during the two-phase menstrual cycle has repeatedly arisen. Some authors (E.P. Maisel, 1965) believe that these transformations are absent. Other researchers found such characteristic changes that they could make a conclusion about the phase of the menstrual cycle based on the epithelium of the tubes [show] .
In particular, A. Yu. Shmeil (1943) discovered in the tubes the same proliferation processes that are observed in the endometrium. S. B. Edelman-Reznik determined that in the follicular phase of the cycle, differentiation of cambial elements into ciliated and secretory cells occurs; at the beginning of the luteal phase, the growth of cilia increases and pronounced secretory swelling of cells appears; at the end of this phase, an increase in the proliferation of cambial cells is observed; rejection of the mucous membrane of the tube does not occur in the menstrual phase of the cycle, but hyperemia, edema and swelling of the endosalpinx stroma develop.
It seems to us that, by analogy with other derivatives of the Müllerian ducts, in which cyclic transformations are clearly recorded (uterus, vagina), cyclic transformations should occur and occur in the tubes, captured by fine microscopic (including histochemical) methods. We find confirmation of this in the work of N.I. Kondrikov (1969), who studied the tubes in various phases of the menstrual cycle, using a number of different techniques for these purposes. In particular, it was determined that the number of different epithelial cells of the endosalpinx (secretory, basal, ciliated, pin-shaped) is not the same along the entire length of the tube. The number of ciliated cells, especially numerous in the mucous membrane of the fimbriae and ampullary section, gradually decreases towards the uterine end of the tube, and the number of secretory cells, minimal in the ampullary section and in the fimbriae, increases towards the uterine end of the tube.
In the first half of the menstrual cycle, the surface of the epithelium is smooth, there are no pin-shaped cells, the amount of RNA gradually increases towards the end of the follicular phase, and the glycogen content in ciliated cells increases. The secretion of the fallopian tubes, determined throughout the menstrual cycle, is located along the apical surface of the secretory and ciliated cells of the endosalpinx epithelium and contains mucopolysaccharides.
In the second half of the menstrual cycle, the height of the epithelial cells decreases, and pin-shaped cells appear (the result of the release of secretory cells from the contents). The amount of RNA and glycogen content decrease.
In the menstrual phase of the cycle, mild swelling of the tube is noted; lymphocytes, leukocytes, and erythrocytes are found in the lumen, which allowed some researchers to call such changes “physiological endosalpingitis” (Nassberg E. A.), with which N. I. Kondrikov (1969) rightly did not agrees, attributing such changes to the reaction of the endosalpinx to the entry of red blood cells into the tube.
Blood supply of the fallopian tubes [show] .
The blood supply to the fallopian tubes occurs through the branches of the uterine and ovarian arteries. O.K. Nikonchik (1954), using the method of thin filling of vessels, found that there are three options for blood supply to the pipes.
- The most common type of vascular supply is when the tubal artery departs in the fundus from the bottom branch of the uterine artery, then passes along the lower edge of the tube and supplies blood to its proximal half, while the ampullary section receives a branch extending from the ovarian artery in the area of the ovarian hilum.
- A less common option is when the tubal artery departs directly from the uterine in the area of the bottom branch, and a branch from the ovarian artery approaches the ampullary end.
- Very rarely, the entire length of the tube is supplied with blood due to vessels originating only from the uterine artery.
Throughout the entire length of the tube, the vessels have a predominantly perpendicular direction to its length and only at the very fimbriae do they take a longitudinal direction. This feature of vascular architectonics must be taken into account during conservative operations on pipes and stomatoplasty (V.P. Pichuev, 1961).
The venous tubal system is located in the subserous and muscular layers in the form of plexuses, running mainly along the round uterine ligament and in the mesosalpinx area.
Lymph from all layers of the fallopian tube is collected in the subserous plexus, from where, through 4-11 extraorgan draining lymphatic vessels, it is directed to the subovarian lymphatic plexus, and then along the ovarian lymphatic vessels to the para-aortic lymph nodes. The intraorgan architecture of the lymphatic vessels of the fallopian tubes, as shown by L. S. Umanskaya (1970), is quite complex and each layer has its own characteristics; it also changes depending on age.
Innervation of the fallopian tubes [show] .
The innervation of the fallopian tubes was studied in detail by A. S. Slepykh (1960). According to him, the main source of innervation should be considered the uterovaginal plexus, which is part of the pelvic plexus. Most of the fallopian tube is innervated from this source, with the exception of the fimbrial end.
Postganglionic fibers emanating from the uterovaginal plexus reach the fallopian tubes in two ways. In greater numbers, they, originating in the ganglia located on the sides of the cervix, rise up the posterolateral wall of the uterus and reach the tubal-uterine angle, where they change their direction to horizontal, bending at a right angle. These nerve trunks give off fibers that approach the tube and branch in the thickness of its wall, ending on the epithelium in the form of button-shaped thickenings. Part of the nerve fibers, leaving the same ganglia, goes directly to the free part of the tube, following between the leaves of the broad ligament parallel to the rib of the uterus.
The second source of innervation of the fallopian tubes is the ovarian plexus, which in turn is a derivative of the caudally located ganglia of the solar plexus.
The third source of innervation of the fallopian tubes is the fibers of the external spermatic nerve.
The interstitial and isthmic parts of the tube have the largest number of nerve fibers. The innervation of the fallopian tubes is mixed; they receive both sympathetic and parasympathetic fibers.
Kubo et al. (1970) expressed the idea of autonomy of the innervation of the fallopian tubes. They examined the tubes of 16 women aged 22 to 41 years. It has been established that the fluorescence of norepinephrine is different in the fimbrial, ampullary and isthmic parts and is not observed in the endosalpinx (epithelial cells). Cholinesterase, usually found in nerve fibers, was rarely detected in the ampullary and fimbrial regions. Monoamine oxidase was found only in the cytoplasm of epithelial cells. These data served as the basis for the authors to conclude that the muscle tissue of the fallopian tubes is similar to the muscle tissue of blood vessels and that the transmission of impulses in the nerve endings is probably of an adrenergic nature.
Physiology of the fallopian tubes. The main function of the fallopian tubes should be considered to be the transport of a fertilized egg to the uterus. Back in 1883, A. Ispolatov established that the advancement of the egg does not occur passively, but due to the peristalsis of the tubes.
The general picture of the contractile activity of the fallopian tubes can be presented as follows: peristaltic contractions of the tubes occur with a general wave of peristalsis directed towards the ampulla or uterus, the tubes can perform pendulum-like movements, while the ampullary section has a complex movement, designated as turbinal. In addition, due to contractions of the predominantly annular layer of muscles, a change in the lumen of the tube itself occurs, i.e., the wave of contraction can move along the axis of the tube, either increasing the tone in one place or decreasing it in another.
Already at the very early stages of studying the transport of the egg through the tubes, it was discovered that the nature of the contractions of the tube and its movements in space depend on the influence of the ovary. Thus, back in 1932, Dyroff established that by the period of ovulation a woman’s tube changes its position and shape, its funnel expands, the fimbriae cover the ovary and the egg at the moment of ovulation enters directly into the lumen of the tube. This process was called the "egg perception mechanism." The author found that on average up to 30-40 contractions of the tube occur per minute. These data were confirmed by a number of other studies.
A very significant contribution to this section was made by A. I. Osyakina-Rozhdestvenskaya (1947). Using the Kehrer-Magnus technique, she discovered that if there are no ovarian influences (menopause), the tube does not react to irritation and does not contract (Fig. 2). In the presence of growing follicles, the tone and excitability of the tube increase sharply, the tube reacts to the slightest influence by changing the number of contractions and moving the convolutions, lifting and moving towards the ampullary end. Contractions often become spastic, without a wave directed towards the abdominal or uterine region, that is, there are no contractions that could ensure the advancement of the egg. At the same time, it was established that movements of the ampulla can provide the “egg perception phenomenon”, since the ampulla, in response to irritation, approaches the ovary (Fig. 3).
If there is a functioning corpus luteum in the ovaries, the tone and excitability of the tubes decrease, and muscle contractions acquire a certain rhythm. The wave of contraction can move along the length, for example, during this period, a poppy grain passes through the middle and isthmic sections in 4-6 hours (Fig. 4), while in the first phase of the cycle the grain almost does not move. Often during this period, the so-called properistaltic wave of contractions is determined - from the ampulla of the tube to the uterus.
A.I. Osyakina-Rozhdestvenskaya also established that, depending on the predominance of one or another ovarian hormone, various deviations in the rhythm of the motor function of the tubes are possible.
R. A. Osipov (1972) conducted an experimental observation on 24 fallopian tubes removed during surgery. Both spontaneous contractions and the effect of oxytocin and pulsed direct current electrical stimulation on them were studied. It was found that under normal conditions, in the first phase of the cycle, the longitudinal muscles are most active, and in the second phase, the circular muscles are most active. During the inflammatory process, contractions of the tube muscles are weakened, especially in the second phase of the cycle. Stimulation of contractions with oxytocin and pulsed electrical current was effective.
Similar studies have been conducted in women using kymographic pertubation. The resulting tubegrams were assessed by the value of tone (minimum pressure), maximum pressure (maximum amplitude), and contraction frequency (number of contractions per minute). In healthy women (control group), spontaneous contractions of the tubes in the first and second phases of the menstrual cycle were directly dependent on the hormonal activity of the ovaries: in the first phase they were more frequent, but weaker than in the second, tone and maximum amplitude compared to the second phase were higher. In the second phase, contractions were more rare, but strong, and the tone and maximum amplitude decreased (Fig. 5).
The inflammatory process caused a decrease in the frequency and strength of contractions. Oxytocin improved tubal contractions only in women with unchanged tone; in the presence of sactosalpimx, oxytocin had no effect at all. Similar data were obtained regarding electrical stimulation.
Hauschild and Seewald in 1974 repeated the experiments of A.I. Osyakina-Rozhdestvenskaya on tubes removed during surgery in women. They showed that antispasmodics cause almost complete inhibition of the contractile activity of the tubes. In addition, it was found that the intensity and amplitude of spontaneous contractions were highest during pregnancy and lowest in menopausal women.
The obligatory participation of ovarian hormones in the motor function of the tubes was confirmed by other studies performed at a later time. Thus, E. A. Semenova (1953), using the kymography method, discovered in the first phase of the cycle a high tone and antiperistaltic nature of the contractions, during which the movement of iodolipol into the abdominal cavity occurred very quickly, in the second phase it was delayed due to peristaltic contractions of the tubes direction from the ampullary end to the isthmic end.
Blanco et al. (1968) conducted a direct study of contractions of the fallopian tubes during operations in 13 patients. A method was used to directly record changes in intratubal pressure by inserting a thin catheter filled with saline into the tube. The contractions of the tubes had a certain rhythm; every 20 s the intratube pressure increased by approximately 2 mm Hg. Art. Periodically, this basal activity was interrupted by the appearance of 1-3 more intense contractions, and there was also an increase in the tone of the tubal muscles, giving a wave lasting 6-8 minutes. In several cases, intrauterine and intratubal pressure were recorded simultaneously: no parallelism was detected between contractions of the uterus and tubes, but when a contraceptive was introduced into the uterine cavity, a sharp increase in contractions of the tubes and an increase in their tone were noted. Intravenous administration of oxytocin had a similar effect.
Coutinho (1973) found that the contractility of longitudinal and circular muscle fibers is autonomous. The shortening of the pipe as a result of contractions of the longitudinal layer is asynchronous with the narrowing of its lumen caused by the contraction of the circular layer. The latter is more sensitive to pharmacological stimulation by adrenergic agents than the longitudinal layers.
In 1973, A. S. Pekki, using the cine-radiography method with simultaneous observation on a television screen, determined that in the second phase of the menstrual cycle, on the one hand, there is relaxation of the sphincters of the fallopian tubes, and on the other, a slow movement of iodolipol through the tubes. It seemed that the movement of the contrast agent in this phase of the cycle occurs due to the pressure created when the fluid is pumped, and not due to the tube's own contractions. This condition is quite explainable by the fact that in the second phase of the cycle the wave of contractions of the tubes is directed primarily towards the uterus.
Erb and Wenner (1971) studied the effects of hormonal and neurotropic substances on fallopian tube contractions. It turned out that the sensitivity of the tubal muscles to adrenaline in the secretion phase is 9 times lower than in the proliferation phase. This decrease depends on the level of progesterone in the blood. A comparison of the reaction of the tubes with the reaction of the myometrium revealed their identity in responses to neurotropic effects. In the secretion phase, tubal movements and sensitivity to acetylcholine are not inhibited by ovarian hormones.
Special kymographic studies of the function of the sphincter of the fallopian tubes depending on the use of hormonal and intrauterine contraceptives were carried out by Kamal (1971). It has been found that the administration of steroids increases the tone of the sphincter, and intrauterine contraceptives can cause its spasm.
Interesting are the observations of Mikulicz-Radecki, who during operations observed that by the time of ovulation, the fimbriae of the tube, due to increased blood supply, swell, become elastic and cover the ovary, which ensures that the egg, after rupture of the follicle, enters directly into the lumen of the tube. This confirmed the data of Dyroff (1932).
It is possible that the fluid flow that occurs after ovulation and directed to the fimbriae also plays a certain role in the mechanism of egg perception. At the VII International Congress on Fertility and Infertility (1971), a film was shown in which the moment of ovulation in animals was filmed. It was clearly visible how an egg literally flies out of the ruptured follicle, surrounded by granulosa cells, and how this ball is directed towards the fimbriae of the tube, located at some distance from the follicle.
An important question is the time during which an egg that enters the tube moves to the uterus. Croxato and Fuentealba (1971) determined the time of transport of the egg from the ovulated ovary to the uterus in healthy women and in those treated with megestrol acetate (a progestin). It turned out that in healthy women the shortest duration of egg transport was 3 days, the longest - 4 days after ovulation, while when taking megestrol this duration increased to 8 days.
In recent years, attention has been drawn to the study of the role of prostaglandins in female reproductive function. As reported in the literature summary by Pauerstein, prostaglandin E has been found to cause tubal relaxation, while prostaglandin F stimulates tubal contractility in humans. The response of fallopian tube muscle tissue to prostaglandins depends on the level and nature of the steroids produced by the ovaries. Thus, progesterone increases the susceptibility of the fallopian tubes to the action of prostaglandin E 1 and reduces it to prostaglandin F 2α. During the period of preovulatory increase in estradiol content, the synthesis of prostaglandins in the tissue of the fallopian tubes increases. This process reaches its highest level at the moment when the isthmic section of the oviduct becomes most sensitive to the effects of prostaglandin F 2α. The development of this mechanism leads to an increase in the muscle tone of the isthmic section of the tubes and their closure, which prevents the premature entry of the fertilized egg into the uterine cavity. An increase in progesterone production increases susceptibility to prostaglandin E, causes an opposite state in the muscle tissue of the isthmic section of the oviducts and promotes the entry of the fertilized egg into the uterus.
Thus, the transport of the egg from the ovary to the uterus is carried out due to active contractions of the muscles of the tubes, which in turn are under the influence of ovarian hormones. These data simultaneously explain such a large difference between the rate of restoration of tubal patency under the influence of conservative or surgical treatments and the rate of pregnancy. It is not enough to restore patency; it is necessary to preserve or restore the transport function of the pipe.
Do the cilia of the ciliated epithelium play any role in the movement of the egg? Opinions on this issue vary. Some authors believe that cilia contribute to the movement of the egg, while others deny this possibility.
N.I. Kondrikov (1969), based on determining the structural features of various parts of the fallopian tubes and discovering the different composition of the epithelial secretion, comes to the same opinion as expressed by Decker. It boils down to the fact that different sections of the tubes have different functions: fimbriae, apparently, capture the egg, the complex branched relief of the folds of the mucous membrane of the ampullary section promotes capacitation of the egg (release from the membranes, ripening); the functional significance of the isthmic department lies in the secretion of substances necessary for the life of the fetal egg.
Mognissi (1971) believes that the fallopian tubes not only perform a transport function, but are also the place where the egg and developing embryo are nourished in the first stages due to intratubal fluid. In the latter, the author determined protein and amino acids. The total amount of protein was found to be 3.26%. Immunoelectrophoretic study of the liquid revealed the presence of 15 types of proteins. An α-glycoprotein was discovered that is absent in the blood and can therefore be classified as a specifically tubal protein. 19 free α-amino acids were also identified. The content of amino acids in intratubal fluid was higher in the proliferative and lower in the luteal phase of the menstrual cycle.
Research by Chang (1955) and others showed that there is a special phenomenon of sperm maturation that occurs in the female genital tract and is called capacitation. Without the ripening process, it is impossible for sperm to penetrate the membranes of the egg. The time required for capacitation varies between animals and ranges from 4 to 8 hours. Edwards et al. (1969) found that in apes and humans there is also a process of capacitation, in which at least two factors participate: one of them acts in the uterus, the other in the oviducts. Thus, another factor has been established that influences the phenomenon of fertilization and the origin of which is related to the function of the tubes.
So, the fallopian tubes perform the function of receiving the egg, fertilization occurs in them, and they also transfer the fertilized egg to the uterus; During the period of passage through the tubes, the egg is in an environment that supports its vital activity and provides optimal conditions for the initial stages of embryo development. These conditions can be met with the anatomical and functional usefulness of the fallopian tubes, which depends on the correctness of their structure and the normal hormonal activity of the ovary.
Pathological anatomy and physiology of pipes. Congenital absence or underdevelopment of one of the tubes is extremely rare. Underdevelopment of both tubes is obligatory in combination with hypoplasia of the uterus and ovaries. A characteristic feature of the pipes in this case is the preservation of spiral tortuosity and a higher location of the ampullary sections compared to the norm. The pipes are not located strictly horizontally, but have an oblique (upward) direction and are called infantile. Due to insufficient contractile activity during salpingography, the contrast agent in such a tube is not divided into separate sections; the diameter of the tube lumen is the same throughout. During cinosalpingography (A.S. Pekki), the contrast agent flows out of the ampoule not in frequent drops, but in a thin, slowly moving stream. The described picture normally occurs in girls before puberty.
During menopause, the tubes become thin, straight, with ampullary sections sluggishly descending into the depths of the pelvis; they do not respond to mechanical and other irritations; the contrast agent moves only due to increasing pressure in the filling uterus.
Thus, in some cases, inferior development and function of a normal tube structure can cause infertility due to impaired egg transport. However, the main cause of dysfunction of the fallopian tubes should be recognized as their anatomical changes that develop directly in the layers of the tube or in the surrounding (or close to the tubes) tissues and organs. Such reasons primarily include various inflammatory changes.
Features of the topography of the pipes determine their most frequent damage by the inflammatory process. This applies equally to both specific diseases (tuberculosis) and general septic infection.
With the development of an infectious inflammatory process, endosalpingitis occurs first. Due to the thin wall of the tube, changes very quickly spread to its muscular and serous layers, which leads to the development of salpingitis. When inflammation begins from the peritoneum, the process also quickly spreads to the entire tube. In this case, the appearance of the pipe changes: it thickens unevenly, takes on a distinct appearance, bends, closed chambers can form along the channel, since the swelling of the folds of the mucous membrane and the desquamation of the epithelium leads to gluing of the folds together.
Initially, during inflammation, hyperemia and swelling of tissues occur with the formation of leukocyte or lymphocytic infiltrates, located mainly at the tops of the folds of the mucous membrane, the small cell infiltrate penetrates into the muscle layers, and pus with a large admixture of destroyed epithelium accumulates in the lumen of the tube. As the acute period subsides, the leukocyte reaction decreases and monocytoid and plasma cells, as well as lymphocytes, begin to predominate in the infiltrate. In the chronic stage, small cell infiltrates are detected in the endosalpinx and muscle layers, located mainly around vessels whose intima is thickened (endovasculitis). The swelling of the layers of the tube is insignificant, but the configuration of the outgrowths of the mucous membrane changes - they become flattened, and sometimes glued together. In some cases, penetration of epithelial islands into the muscle layers is noted.
N.I. Kondrikov (1969) found morpho-functional changes in all layers of the fallopian tubes in chronic salpingitis. As the chronic inflammatory process progresses, collagen fibers grow in the stroma of the folds of the mucous membrane, the muscular wall of the fallopian tubes and under the serous cover. Blood vessels gradually undergo obliteration, and acidic mucopolysaccharides accumulate around them. Functional changes also develop, expressed in a decrease in the level of RNA and glycogen and a decrease in the content of glycoproteins in the secretion of the fallopian tubes. All these changes can disrupt the transport of the egg or cause its death.
Finally, we should dwell on the consequences of the inflammation in the form of scar-adhesive changes. If during the inflammatory process there were no areas of significant necrosis in the tube, a gradual restoration of the mucous membrane occurs with the restoration of the patency of the tube and its function. If the process of tissue destruction was significant, the inflammation ends with scarring.
V.K. Rymashevsky and D.S. Zaprudskaya (1975) studied the content of acidic mucopolysaccharides in 43 fallopian tubes removed from women with chronic salpingoophoritis. It turned out that with a relatively short duration of the disease, their content is quite high, and then decreases somewhat. When the disease lasts up to 10 years or more, it increases again, which confirms the gradually increasing disorganization of connective tissue that occurs during inflammation.
L. P. Drobyazko et al. (1970) subjected 32 fallopian tubes removed during infertility surgery to serial microscopic examination. Based on the nature of the morphological changes found in the wall of the fallopian tube, three groups were distinguished.
In the first group (8 observations), macroscopically the fallopian tubes were tortuous, slightly thickened with the presence of dense adhesions of the peritoneal cover. During microscopy, the lumen of the fallopian tube was deformed in places, the folds of the mucous membrane were hypertrophied in some places, branching, and in places fused together; in some cases, the mucous membrane of the tube was somewhat atrophic, with poorly developed folds. The muscle layer is mostly without features, sometimes atrophic. On the part of the peritoneum, in some cases moderate swelling and fibrin deposits were detected, in others - extensive growths of connective tissue. In all cases, moderate lymphocytic infiltration was noted. Thus, in this group there were phenomena of chronic salpingitis with more or less pronounced structural changes predominant in the mucous and serous membranes of the fallopian tube. It should be noted that the majority of women in this group had no data on previous inflammatory process of the genitals; infertility was more often secondary, lasting up to 5 years.
In the second group (11 observations), pronounced macroscopic changes in the fallopian tubes were noted: the presence of peritubar adhesions distorting the shape of the tube, focal compactions with obliteration of the tube lumen or, in places, with its expansion. Microscopically, deformation of the tube lumen was more often observed. The folds of the mucous membrane in some areas were atrophic, in some places they protruded into the expanded lumen of the tube in the form of branched growths. Often they were hypertrophied, swollen, fused together, forming closed small cells filled with serous exudate. In small cells, metaplasia of columnar epithelium into cubic epithelium was revealed, in large cells - into squamous epithelium. In most hypertrophied folds, excessive growth of connective tissue with many newly formed small vessels is noted. Sclerosis is evident in the submucosal layer. The muscle layer is unevenly developed - in some places it is atrophic, in others it is hypertrophied with layers of connective tissue of varying degrees of maturity. Sometimes scattered, cyst-like formations of various sizes and shapes, lined with cuboidal epithelium, were found in the muscular and subperitoneal layers. Against the same background, a significant number of lymphatic slits and blood vessels of different calibers were noted, most of them small, with a thickened sclerotic wall. Excessive growth of connective tissue was more often observed in the peritoneum. In all layers of the tube wall there was focal lymphoid infiltration with the presence of single plasma cells. In some cases, accumulations of neutrophilic leukocytes and eosinophils were found. Consequently, in the second group, the phenomena of chronic salpingitis with pronounced sclerosis of all layers of the pipe wall, especially the mucous and submucosal layers, were noted. In this group, the adhesions of the peritoneal covering, deformation and obliteration of the lumen of the tube are more pronounced than in the first group. All women in this group had suffered B1 inflammation of the uterine appendages in the past. For the majority, infertility was primary, for some it was secondary, after an abortion. The duration of infertility is 5 years or more.
In the third group (13 observations), macroscopically the walls of the fallopian tubes were thickened, the fimbrial ends were sealed. More often than in the previous group, focal compactions were encountered, narrowing and sometimes obliterating the lumen of the tube. Adhesions were more common, involving the uterus and ovaries. On microscopic examination, the folds of the mucous membrane were thickened throughout and fused together. In places of greatest thickening of the pipe, its lumen was either absent or narrowed and deformed. As a result of adhesions, the mucous membrane formed network-like structures, their epithelium was flattened. The cells are filled with contents containing a small number of desquamated epithelial cells, erythrocytes, and leukocytes. The muscle layer is hypertrophied, partly atrophic with excessive development of connective tissue of varying degrees of maturity: in the form of either delicate, network-like fibrils, or coarser and thicker layers with signs of hyalinosis. In the muscular and subperitoneal layers, scattered cyst-like formations of various shapes were often found - round, oval, bay-shaped. Their walls consisted of a connective tissue base, were lined with cubic or squamous epithelium, and a serous secretion with a small number of formed elements was revealed in the lumens. Along with this, a large number of lymphatic slits and blood vessels of different sizes, often small, were noted. The walls of the vessels are thickened due to the development of rough connective tissue with partial hyalinosis and an almost complete absence of smooth muscle elements. On the part of the peritoneum, massive development of fibrous tissue with significant hyalinosis was observed. In some preparations, concentric deposits of lime (psammotic bodies) were found in the mucosal and submucosal layers. There was uneven lympho-leukocyte infiltration in all layers. In some cases, focal accumulations of leukocytes were observed.
In the third group, rather gross morphological changes were found: pronounced deformation, often the absence of a tube lumen as a result of the proliferation of the mucous membrane, significant sclerosis of all layers of the wall of the fallopian tube, a rougher and more massive development of fibrous tissue in the peritoneal cover. In each observation of this group, cyst-like formations were noted in the muscular and subperitoneal layers, fibrosis and hyalinosis of the vascular walls.
In some cases, phenomena of purulent salpingitis were observed, combined with gross irreversible changes in the pipe wall.
All patients in this group suffered inflammation of the uterine appendages with pronounced clinical manifestations. In some women, the disease was long-lasting and often worsened; some had purulent inflammation of the uterine appendages in the past. Infertility, both primary and secondary, lasted from 6 to 9 years.
Saccular formations of tubes (sactosalpinx) arise as a result of gluing fimbriae together and closing the lumen of the tube in the ampullary section. In this case, the products of inflammation are retained, sometimes stretching the resulting cavity to quite large sizes. Based on the nature of the contents, there are pyosalpinx (pus), hydrosalpinx (serous fluid), hematosalpinx (blood), and oleosalpinx (oily contrast fluid injected during an X-ray examination). The walls of the saccular formation can have different thicknesses; as a rule, the inner surface is either a velvety, somewhat thickened or, conversely, an atrophied endosalpinx without folds.
Tubal-ovarian inflammatory formations arise due to the topographic proximity of the tubes and ovaries, the commonality of their circulatory and lymphatic systems. Sometimes, upon examination, it is difficult to distinguish the boundaries of the tubes and ovaries in these conglomerates, which often include inflammatory cavities common to them.
It is difficult to identify any specific pathomorphological changes in the tubes that are pathognomonic for a certain type of infection, with the exception of tuberculosis, in which these changes are very characteristic. Of the organs of the reproductive system, tuberculosis most often affects the tubes. As a rule, the process begins with damage to the fimbriae and their gluing, which leads to the formation of sactosalpinx with the accumulation of decay products (caseous masses). Very quickly the muscle layer and serous membrane are involved in inflammation. The detection during this period of elements of productive inflammation - specific granulomas - is undoubted evidence of the ongoing tuberculosis process. Post-tuberculosis phenomena are much more difficult to diagnose, when infiltrative-productive ones are replaced by cicatricial, sclerosing changes that cover all layers of the tube. Sometimes calcified lesions are found.
The patency of the tubes can be influenced by foci of endometriosis, the development of which is associated with implantation of the endometrium in the tubes due to antiperistaltic reflux of menstrual blood or intrauterine manipulations (curettage of the mucous membrane, blowing, hysterography, etc.). Endometrioid heterotopias in the tubes, the frequency of which has been increasing in recent years, can cause infertility (complete occlusion of the tube) or the development of tubal pregnancy.
Changes in the conditions of egg transport due to a direct change in the lumen as a result of the development of a tumor process inside the tube occur relatively rarely. Isolated cases of detection of fibroma, myxoma and lymphangioma of the fallopian tubes have been described.
The lumen of the tube, its length, location in space can change during tumor processes in the uterus (fibroids) or ovaries (cystoma), when, on the one hand, the topography of the organ changes, on the other hand, the oppressive influence of the tumor itself affects. Changes in the pipes in these cases will depend on changes in the shape and volume of neighboring organs.
Organs of the female reproductive system include: 1) internal(located in the pelvis) - female gonads - ovaries, fallopian tubes, uterus, vagina; 2) external- pubis, labia minora and majora and clitoris. They reach full development with the onset of puberty, when their cyclic activity is established (ovarian-menstrual cycle), which continues during the woman’s reproductive period and ceases with its completion, after which the organs of the reproductive system lose their function and atrophy.
Ovary
Ovary performs two functions - generative(formation of female reproductive cells - ovogenesis) And endocrine(synthesis of female sex hormones). On the outside he is dressed cubic superficial epithelium(modified mesothelium) and consists of cortical And medulla(Fig. 264).
Ovarian cortex - wide, not sharply separated from the brain. Its bulk consists of ovarian follicles, formed by germ cells (ovocytes), which are surrounded by follicular epithelial cells.
Ovarian medulla - small, contains large convoluted blood vessels and special chyle cells.
Ovarian stroma represented by dense connective tissue tunica albuginea, lying under the surface epithelium, and a peculiar spindle cell connective tissue, in which spindle-shaped fibroblasts and fibrocytes are densely arranged in the form of swirls.
Oogenesis(except for the final stage) occurs in the ovarian cortex and includes 3 phases: 1) reproduction, 2) growth and 3) maturation.
Breeding phase Oogonia occurs in utero and is completed before birth; Most of the resulting cells die, the smaller part enters the growth phase, turning into primary oocytes, the development of which is blocked in prophase I of the meiotic division, during which (as during spermatogenesis) an exchange of chromosome segments occurs, providing genetic diversity of gametes.
Growth phase The oocyte consists of two periods: small and large. The first is noted before puberty in the absence of hormonal stimulation.
simulations; the second occurs only after it under the influence of follicle-stimulating hormone (FSH) of the pituitary gland and is characterized by the periodic involvement of follicles in cyclic development, culminating in their maturation.
Maturation phase begins with the resumption of division of primary oocytes in mature follicles immediately before the onset of ovulation. Upon completion of the first division of maturation, secondary oocyte and a small cell, almost devoid of cytoplasm - first polar body. The secondary oocyte immediately enters the second division of maturation, which, however, stops at metaphase. During ovulation, the secondary oocyte is released from the ovary and enters the fallopian tube, where, in the case of fertilization by sperm, it completes the maturation phase with the formation of a haploid mature female reproductive cell (ovules) And second polar body. The polar bodies are subsequently destroyed. In the absence of fertilization, the germ cell undergoes degeneration at the secondary oocyte stage.
Oogenesis occurs with constant interaction of developing germ cells with epithelial cells in the follicles, changes in which are known as folliculogenesis.
Ovarian follicles immersed in the stroma and consist of primary oocyte, surrounded by follicular cells. They create the microenvironment necessary to maintain the viability and growth of the oocyte. Follicles also have an endocrine function. The size and structure of the follicle depend on the stage of its development. There are: primordial, primary, secondary And tertiary follicles(see Fig. 264-266).
Primordial follicles - the smallest and most numerous, located in the form of clusters under the tunica albuginea and consist of small primary oocyte, surrounded single-layer squamous epithelium (follicular epithelial cells).
Primary follicles consist of larger primary oocyte, surrounded one layer of cubic or columnar follicular cells. Between the oocyte and follicular cells it first becomes noticeable transparent shell, having the appearance of a structureless oxyphilic layer. It consists of glycoproteins, is produced by the oocyte and helps to increase the surface area of the mutual exchange of substances between it and the follicular cells. As further
As follicles grow, the thickness of the transparent membrane increases.
Secondary follicles contain continuing to grow primary oocyte, surrounded by a shell of multilayer cuboidal epithelium, whose cells divide under the influence of FSH. A significant number of organelles and inclusions accumulate in the cytoplasm of the oocyte; cortical granules, which further participate in the formation of the fertilization membrane. The content of organelles that form their secretory apparatus also increases in follicular cells. The transparent shell thickens; microvilli of the oocyte penetrate into it, contacting the processes of follicular cells (see Fig. 25). thickens follicle basement membrane between these cells and the surrounding stroma; the latter forms connective tissue membrane (theca) of the follicle(see Fig. 266).
Tertiary (vesicular, antral) follicles formed from secondary ones due to secretion by follicular cells follicular fluid which first accumulates in small cavities of the follicular membrane, which later merge into a single follicle cavity(antrum). Oocyte is inside oviparous tubercle- accumulations of follicular cells protruding into the lumen of the follicle (see Fig. 266). The remaining follicular cells are called granulosa and produce female sex hormones estrogens, the levels of which in the blood increase as the follicles grow. The theca of the follicle is divided into two layers: outer layer of theca contains fibroblasts theca, in inner layer of theca steroid-producing endocrinocytes theca.
Mature (preovulatory) follicles (Graafian follicles) - large (18-25 mm), protrude above the surface of the ovary.
Ovulation- rupture of a mature follicle with the release of an oocyte from it, as a rule, occurs on the 14th day of a 28-day cycle under the influence of a surge of LH. A few hours before ovulation, the oocyte, surrounded by cells of the egg-bearing tubercle, separates from the wall of the follicle and floats freely in its cavity. In this case, the follicular cells associated with the transparent membrane elongate, forming the so-called radiant crown. In the primary oocyte, meiosis (blocked in prophase of division I) is resumed with the formation secondary oocyte And first polar body. The secondary oocyte then enters the second division of maturation, which is blocked in metaphase. Rupture of the follicle wall and covering
The destruction of the ovarian tissue occurs in a small thinned and loosened protruding area - stigma. In this case, an oocyte surrounded by cells of the corona radiata and follicular fluid are released from the follicle.
Corpus luteum is formed as a result of differentiation of granulosa and theca cells of the ovulated follicle, the walls of which collapse, forming folds, and in the lumen there is a blood clot, which is later replaced by connective tissue (see Fig. 265).
Development of the corpus luteum (luteogenesis) includes 4 stages: 1) proliferation and vascularization; 2) ferruginous metamorphosis; 3) flourishing and 4) reverse development.
Stage of proliferation and vascularization characterized by active proliferation of granulosa and theca cells. Capillaries grow into the granulosa from the inner layer of the theca, and the basement membrane separating them is destroyed.
Stage of ferruginous metamorphosis: granulosa and theca cells turn into polygonal light-colored cells - luteocytes (granulosa) And techies), in which a powerful synthetic apparatus is formed. The bulk of the corpus luteum consists of large light granulosa luteocytes, along its periphery lie small and dark luteocytes theca(Fig. 267).
Blooming stage characterized by the active function of luteocytes producing progesterone- female sex hormone that promotes the occurrence and progression of pregnancy. These cells contain large lipid droplets and are in contact with an extensive capillary network
(Fig. 268).
Reverse development stage includes a sequence of degenerative changes in luteocytes with their destruction (luteolytic body) and replacement with a dense connective tissue scar - whitish body(see Fig. 265).
Follicular atresia- a process involving growth arrest and destruction of follicles, which, affecting small follicles (primordial, primary), leads to their complete destruction and complete replacement with connective tissue, and when developing in large follicles (secondary and tertiary) causes their transformation with the formation atretic follicles. With atresia, the oocyte (only its transparent shell is preserved) and granulosa cells die, while the cells of the theca interna, on the contrary, grow (Fig. 269). For some time, the atretic follicle actively synthesizes steroid hormones,
is subsequently destroyed, replaced by connective tissue - a whitish body (see Fig. 265).
All described sequential changes in the follicles and corpus luteum, occurring cyclically during the reproductive period of a woman’s life and accompanied by corresponding fluctuations in the levels of sex hormones, are called ovarian cycle.
Chyle cells form clusters around capillaries and nerve fibers in the area of the ovarian hilum (see Fig. 264). They are similar to interstitial endocrinocytes (Leydig cells) of the testicle, contain lipid droplets, a well-developed agranular endoplasmic reticulum, and sometimes small crystals; produce androgens.
Oviduct
The fallopian tubes are muscular tubular organs that stretch along the broad ligament of the uterus from the ovary to the uterus.
Functions fallopian tubes: (1) capture of the oocyte released from the ovary during ovulation and its transfer towards the uterus; (2) creating conditions for the transport of sperm from the uterus; (3) providing the environment necessary for fertilization and initial development of the embryo; (5) transfer of the embryo into the uterus.
Anatomically, the fallopian tube is divided into 4 sections: a funnel with a fringe that opens in the ovary region, an expanded part - the ampulla, a narrow part - the isthmus and a short intramural (interstitial) segment located in the wall of the uterus. The wall of the fallopian tube consists of three membranes: mucous membrane, muscle And serous(Fig. 270 and 271).
Mucous membrane forms numerous branching folds, strongly developed in the infundibulum and ampulla, where they almost completely fill the lumen of the organ. In the isthmus these folds are shortened, and in the interstitial segment they turn into short ridges (see Fig. 270).
Epithelium mucous membrane - single-layer columnar, formed by two types of cells - ciliated And secretory. Lymphocytes are constantly present in it.
Own record mucous membrane - thin, formed by loose fibrous connective tissue; the fimbria contains large veins.
Muscularis thickens from the ampulla to the intramural segment; consists of vaguely demarcated thick internal circular
and thin outer longitudinal layers(see Fig. 270 and 271). Its contractile activity is enhanced by estrogens and inhibited by progesterone.
Serosa characterized by the presence under the mesothelium of a thick layer of connective tissue containing blood vessels and nerves (subserosal base), and in the ampullar region - bundles of smooth muscle tissue.
Uterus
Uterus is a hollow organ with a thick muscular wall in which the development of the embryo and fetus occurs. The fallopian tubes open into its expanded upper part (body), the narrowed lower (Cervix) protrudes into the vagina, communicating with it through the cervical canal. The wall of the uterine body consists of three membranes (Fig. 272): 1) mucous membrane (endometrium), 2) muscular layer (myometrium) and 3) serous membrane (perimetry).
Endometrium undergoes cyclic changes during the reproductive period (menstrual cycle) in response to rhythmic changes in hormone secretion by the ovary (ovarian cycle). Each cycle ends with the destruction and removal of part of the endometrium, which is accompanied by the release of blood (menstrual bleeding).
The endometrium consists of a covering single layer columnar epithelium, who is educated secretory And ciliated epithelial cells, And own record- endometrial stroma. The latter contains simple tubular uterine glands, which open onto the surface of the endometrium (Fig. 272). The glands are formed by columnar epithelium (similar to the integumentary epithelium): their functional activity and morphological features change significantly during the menstrual cycle. The endometrial stroma contains fibroblast-like cells (capable of a number of transformations), lymphocytes, histiocytes and mast cells. Between the cells there is a network of collagen and reticular fibers; elastic fibers are found only in the arterial wall. The endometrium has two layers that differ in structure and function: 1) basal and 2) functional(see Fig. 272 and 273).
Basal layer The endometrium is attached to the myometrium and contains the bottoms of the uterine glands, surrounded by stroma with a dense arrangement of cellular elements. It is little sensitive to hormones, has a stable structure and serves as a source of restoration of the functional layer.
Receives nutrition from straight arteries, departing from radial arteries, which penetrate the endometrium from the myometrium. It contains the proximal parts spiral arteries, serving as a continuation of the radial ones into the functional layer.
Functional layer (at its full development) much thicker than the basal one; contains numerous glands and vessels. It is highly sensitive to hormones, under the influence of which its structure and function change; at the end of each menstrual cycle (see below), this layer is destroyed, being restored again in the next. Supplied with blood from spiral arteries, which are divided into a number of arterioles associated with capillary networks.
Myometrium- the thickest lining of the uterine wall - includes three vaguely demarcated muscle layers: 1) submucosal- internal, with an oblique arrangement of bundles of smooth muscle cells; 2) vascular- medium, the widest, with a circular or spiral course of bundles of smooth muscle cells, containing large vessels; 3) supravascular- external, with an oblique or longitudinal arrangement of bundles of smooth muscle cells (see Fig. 272). Between the bundles of smooth myocytes there are layers of connective tissue. The structure and function of the myometrium depend on female sex hormones estrogen, enhancing its growth and contractile activity, which is inhibited progesterone. During childbirth, the contractile activity of the myometrium is stimulated by the hypothalamic neurohormone oxytocin.
Perimetry has a typical structure of the serous membrane (mesothelium with underlying connective tissue); it does not completely cover the uterus - in those areas where it is absent, there is an adventitial membrane. The perimetry contains sympathetic nerve ganglia and plexuses.
Menstrual cycle- natural changes in the endometrium, which repeat on average every 28 days and are conditionally divided into three phases: (1) menstrual(bleeding), (2) proliferation,(3) secretion(see Fig. 272 and 273).
Menstrual phase (days 1-4) in the first two days is characterized by the removal of the destroyed functional layer (formed in the previous cycle) along with a small amount of blood, after which only basal layer. The surface of the endometrium, not covered with epithelium, undergoes epithelialization in the next two days due to the migration of the epithelium from the bottoms of the glands to the surface of the stroma.
Proliferation phase (5-14th days of the cycle) is characterized by increased growth of the endometrium (under the influence estrogen, secreted by the growing follicle) with the formation of structurally formed, but functionally inactive narrow uterine glands, towards the end of the phase, acquiring a corkscrew-like motion. There is active mitotic division of endometrial gland and stroma cells. Formation and growth takes place spiral arteries, few convoluted in this phase.
Secretion phase (15-28th days of the cycle) and is characterized by active activity of the uterine glands, as well as changes in stromal elements and blood vessels under the influence progesterone, secreted by the corpus luteum. In the middle of the phase, the endometrium reaches its maximum development, its condition is optimal for embryo implantation; at the end of the phase, the functional layer undergoes necrosis due to vasospasm. The production and secretion of secretions by the uterine glands begins on the 19th day and intensifies by the 20-22nd. The glands have a convoluted appearance, their lumen is often saccularly stretched and filled with secretion containing glycogen and glycosaminoglycans. The stroma swells, and islands of large polygonal structures form in it. predecidual cells. Due to intensive growth, the spiral arteries become sharply tortuous, twisting in the form of balls. In the absence of pregnancy due to regression of the corpus luteum and a decrease in progesterone levels on days 23-24, the secretion of endometrial glands ends, its trophism worsens and degenerative changes begin. The swelling of the stroma decreases, the uterine glands become folded, saw-toothed, and many of their cells die. The spiral arteries spasm on the 27th day, stopping the blood supply to the functional layer and causing its death. The necrotic and blood-soaked endometrium is rejected, which is facilitated by periodic contractions of the uterus.
Cervix has the structure of a thick-walled tube; it is permeated cervical canal, which begins in the uterine cavity internal throat and ends in the vaginal part of the cervix external pharynx.
Mucous membrane The cervix is formed by epithelium and the lamina propria and differs in structure from the similar lining of the uterine body. Cervical canal characterized by numerous longitudinal and transverse branching palm-shaped folds of the mucous membrane. It's lined single-layer columnar epithelium, which protrudes into its own plate, forming
about 100 branched cervical glands(Fig. 274).
Epithelium of the canal and glands includes two types of cells: numerically predominant glandular mucous cells (mucocytes) And ciliated epithelial cells. Changes in the mucous membrane of the cervix during the menstrual cycle are manifested by fluctuations in the secretory activity of cervical mucocytes, which increases approximately 10 times in the middle of the cycle. The cervical canal is normally filled with mucus (cervical plug).
Epithelium of the vaginal part of the cervix,
as in the vagina, - multilayer flat non-keratinizing, containing three layers: basal, intermediate and superficial. The border of this epithelium with the epithelium of the cervical canal is sharp, passes mainly above the external pharynx (see Fig. 274), but its location is not constant and depends on endocrine influences.
Own record The mucous membrane of the cervix is formed by loose fibrous connective tissue with a high content of plasma cells that produce secretory IgA, which are transferred into the mucus by epithelial cells and ensure the maintenance of local immunity in the female reproductive system.
Myometrium consists predominantly of circular bundles of smooth muscle cells; the content of connective tissue in it is much higher (especially in the vaginal part) than in the myometrium of the body, the network of elastic fibers is more developed.
Placenta
Placenta- a temporary organ formed in the uterus during pregnancy and providing a connection between the organisms of the mother and the fetus, thanks to which the growth and development of the latter occurs.
Functions of the placenta: (1) trophic- providing nutrition to the fetus; (2) respiratory- ensuring fetal gas exchange; (3) excretory(excretory) - removal of fetal metabolic products; (4) barrier- protection of the fetal body from the effects of toxic factors, preventing microorganisms from entering the fetal body; (5) endocrine- synthesis of hormones that ensure the course of pregnancy and prepare the mother’s body for childbirth; (6) immune- ensuring immune compatibility of mother and fetus. It is customary to distinguish maternal And fetal part placenta.
Chorionic plate located under the amniotic membrane; she was educated in
fibrous connective tissue that contains chorionic vessels- branches of the umbilical arteries and umbilical vein (Fig. 275). The chorionic plate is covered with a layer fibrinoid- a homogeneous structureless oxyphilic substance of glycoprotein nature, which is formed by the tissues of the maternal and fetal organism and covers various parts of the placenta.
Chorionic villi originate from the chorionic plate. Large villi branch strongly, forming a villous tree that is immersed in intervillous spaces (lacunae), filled with maternal blood. Among the branches of the villous tree, depending on the caliber, position in this tree and function, several types of villi are distinguished (large, intermediate and terminal). Large ones, in particular stem (anchor) villi perform a supporting function, contain large branches of the umbilical vessels and regulate the flow of fetal blood into the capillaries of small villi. Anchor villi are connected to the decidua (basal plate) cell columns, formed by extravillous cytotrophoblast. Terminal villi move away from intermediate and are an area of active exchange between the blood of the mother and the fetus. The components that form them remain unchanged, but the relationship between them undergoes significant changes at different stages of pregnancy (Fig. 276).
Villous stroma formed by loose fibrous connective tissue containing fibroblasts, mast and plasma cells, as well as special macrophages (Hoffbauer cells) and fetal blood capillaries.
Trophoblast covers the villi from the outside and is represented by two layers - the outer layer syncytiotrophoblastoma and internal - cytotrophoblast.
Cytotrophoblast- a layer of mononuclear cubic cells (Langhans cells) - with large euchromatic nuclei and weakly or moderately basophilic cytoplasm. They maintain their high proliferative activity throughout pregnancy.
Syncytiotrophoblast is formed as a result of the fusion of cytotrophoblast cells, therefore it is represented by extensive cytoplasm of variable thickness with well-developed organelles and numerous microvilli on the apical surface, as well as numerous nuclei that are smaller than in the cytotrophoblast.
Villi in early pregnancy covered with a continuous layer of cytotrophoblast and a broad layer of syncytiotrophoblast with evenly distributed nuclei. Their voluminous, loose stroma of the immature type contains individual macrophages and a small number of poorly developed capillaries, located mainly in the center of the villi (see Fig. 276).
Villi in the mature placenta characterized by changes in the stroma, blood vessels and trophoblast. The stroma becomes looser, macrophages are rare in it, capillaries have a sharply convoluted course, and are located closer to the periphery of the villi; at the end of pregnancy, so-called sinusoids appear - sharply dilated segments of capillaries (unlike the sinusoids of the liver and bone marrow, they are covered with a continuous endothelial lining). The relative content of cytotrophoblast cells in the villi decreases in the second half of pregnancy, and their layer loses its continuity, and by the time of birth only individual cells remain in it. The syncytiotrophoblast becomes thinner, in some places forming thinned areas close to the endothelium of the capillaries. Its nuclei are reduced, often hyperchromatic, form compact clusters (nodes), undergo apoptosis and, together with fragments of the cytoplasm, are separated into the maternal bloodstream. The trophoblast layer is covered from the outside and is replaced by fibrinoid (see Fig. 276).
Placental barrier- a set of tissues that separate the maternal and fetal blood flow, through which two-way exchange of substances occurs between the mother and the fetus. In the early stages of pregnancy, the thickness of the placental barrier is maximum and is represented by the following layers: fibrinoid, syncytiotrophoblast, cytotrophoblast, basement membrane of the cytotrophoblast, connective tissue of the villus stroma, basement membrane of the villus capillary, its endothelium. The thickness of the barrier decreases significantly towards the end of pregnancy due to the tissue changes noted above (see Fig. 276).
Maternal part of the placenta educated basal lamina of the endometrium (basal decidua), from which to intervillous spaces connective tissue septa depart (septa), not reaching the chorionic plate and not completely delimiting this space into separate chambers. The decidua contains special decidual cells, which are formed during pregnancy from predecidual cells appearing in the stroma
endometrium in the secretory phase of each menstrual cycle. Decidual cells are large, oval or polygonal in shape, with a round, eccentrically located light nucleus and acidophilic vacuolated cytoplasm containing a developed synthetic apparatus. These cells secrete a number of cytokines, growth factors and hormones (prolactin, estradiol, corticoliberin, relaxin), which, on the one hand, collectively limit the depth of trophoblast invasion into the uterine wall, on the other, ensure local tolerance of the mother’s immune system towards the allogeneic fetus , which determines the successful course of pregnancy.
Vagina
Vagina- a thick-walled, extensible tubular organ that connects the vestibule of the vagina to the cervix. The vaginal wall consists of three membranes: mucous membrane, muscle And adventitial.
Mucous membrane lined with thick multilayered squamous non-keratinizing epithelium lying on the lamina propria (see Fig. 274). Epithelium includes basal, intermediate And surface layers. It constantly contains lymphocytes, antigen-presenting cells (Langerhans). The lamina propria consists of fibrous connective tissue with a large number of collagen and elastic fibers and an extensive venous plexus.
Muscularis consists of bundles of smooth muscle cells forming two poorly demarcated layers: internal circular And external longitudinal, which continue into similar layers of the myometrium.
Adventitia formed by connective tissue that merges with the adventitia of the rectum and bladder. Contains a large venous plexus and nerves.
Breast
Breast is part of the reproductive system; its structure varies significantly at different periods of life, which is due to differences in hormonal levels. In an adult woman, the mammary gland consists of 15-20 shares- tubular-alveolar glands, which are delimited by strands of dense connective tissue and, diverging radially from the nipple, are further divided into multiple lobules. There is a lot of fat between the lobules
fabrics. The lobes on the nipple open milk ducts, extended areas of which (milky sinuses) located under areola(pigmented areola). The milky sinuses are lined with stratified squamous epithelium, the remaining ducts are lined with single-layer cubic or columnar epithelium and myoepithelial cells. The nipple and areola contain a large number of sebaceous glands, as well as bundles of radial (longitudinal) smooth muscle cells.
Functionally inactive mammary gland
contains a poorly developed glandular component, which consists mainly of ducts. End sections (alveoli) are not formed and have the appearance of terminal buds. Most of the organ is occupied by stroma, represented by fibrous connective and adipose tissue (Fig. 277). During pregnancy, under the influence of high concentrations of hormones (estrogens and progesterone in combination with prolactin and placental lactogen), a structural and functional restructuring of the gland occurs. It includes a sharp proliferation of epithelial tissue with elongation and branching of ducts, the formation of alveoli with a decrease in the volume of adipose and fibrous connective tissue.
Functionally active (lactating) mammary gland formed by lobules consisting of terminal sections (alveoli), filled with milk
com, and intralobular ducts; between the lobules in layers of connective tissue (interlobular septa) interlobular ducts are located (Fig. 278). Secretory cells (galactocytes) contain a developed granular endoplasmic reticulum, a moderate number of mitochondria, lysosomes, and a large Golgi complex (see Fig. 44). They produce products that are secreted by various mechanisms. Protein (casein), and milk sugar (lactose) stand out merocrine mechanism by fusion of the secretory membrane protein granules with plasmalemma. Small lipid droplets merge to form larger ones lipid drops, which are directed to the apical part of the cell and secreted into the lumen of the terminal section along with the surrounding areas of the cytoplasm (apocrine secretion)- see fig. 43 and 279.
Milk production is regulated by estrogens, progesterone and prolactin in combination with insulin, corticosteroids, growth hormone and thyroid hormones. Milk release is ensured myoepithelial cells, which with their processes cover galactocytes and contract under the influence of oxytocin. In the lactating mammary gland, the connective tissue has the form of thin partitions infiltrated with lymphocytes, macrophages, and plasma cells. The latter produce class A immunoglobulins, which are transported into the secretion.
ORGANS OF THE FEMALE GENITAL SYSTEM
Rice. 264. Ovary (general view)
Staining: hematoxylin-eosin
1 - surface epithelium (mesothelium); 2 - tunica albuginea; 3 - cortical substance: 3.1 - primordial follicles, 3.2 - primary follicle, 3.3 - secondary follicle, 3.4 - tertiary follicle (early antral), 3.5 - tertiary (mature preovulatory) follicle - Graafian vesicle, 3.6 - atretic follicle, 3.7 - corpus luteum , 3.8 - stroma of the cortex; 4 - medulla: 4.1 - loose fibrous connective tissue, 4.2 - chyle cells, 4.3 - blood vessels
Rice. 265. Ovary. Dynamics of transformation of structural components - ovarian cycle (diagram)
The diagram shows the progress of transformations in processes oogenesis And folliculogenesis(red arrows), education and development of the corpus luteum(yellow arrows) and follicular atresia(black arrows). The final stage of transformation of the corpus luteum and atretic follicle is the whitish body (formed by scar connective tissue)
Rice. 266. Ovary. Cortical area
Staining: hematoxylin-eosin
1 - surface epithelium (mesothelium); 2 - tunica albuginea; 3 - primordial follicles:
3.1 - primary oocyte, 3.2 - follicular cells (flat); 4 - primary follicle: 4.1 - primary oocyte, 4.2 - follicular cells (cubic, columnar); 5 - secondary follicle: 5.1 - primary oocyte, 5.2 - transparent membrane, 5.3 - follicular cells (multilayered membrane) - granulosa; 6 - tertiary follicle (early antral): 6.1 - primary oocyte, 6.2 - transparent membrane, 6.3 - follicular cells - granulosa, 6.4 - cavities containing follicular fluid, 6.5 - follicular theca; 7 - mature tertiary (preovulatory) follicle - Graafian vesicle: 7.1 - primary oocyte,
7.2 - transparent membrane, 7.3 - egg-bearing tubercle, 7.4 - follicular cells of the follicle wall - granulosa, 7.5 - cavity containing follicular fluid, 7.6 - the theca of the follicle, 7.6.1 - inner layer of the theca, 7.6.2 - outer layer of the theca; 8 - atretic follicle: 8.1 - remains of the oocyte and transparent membrane, 8.2 - cells of the atretic follicle; 9 - loose fibrous connective tissue (ovarian stroma)
Rice. 267. Ovary. Corpus luteum in its prime
Staining: hematoxylin-eosin
1 - luteocytes: 1.1 - granulosa luteocytes, 1.2 - theca luteocytes; 2 - area of hemorrhage; 3 - layers of loose fibrous connective tissue; 4 - blood capillaries; 5 - connective tissue capsule (ovarian stroma compaction)
Rice. 268. Ovary. Corpus luteum area
Staining: hematoxylin-eosin
1 - granulosa luteocytes: 1.1 - lipid inclusions in the cytoplasm; 2 - blood capillaries
Rice. 269. Ovary. Atretic follicle
Staining: hematoxylin-eosin
1 - remains of a destroyed oocyte; 2 - remains of a transparent shell; 3 - glandular cells; 4 - blood capillary; 5 - connective tissue capsule (ovarian stroma compaction)
Rice. 270. Fallopian tube (general view)
I - ampullary part; II - isthmus Staining: hematoxylin-eosin
1 - mucous membrane: 1.1 - single-layer columnar ciliated epithelium, 1.2 - lamina propria; 2 - muscular layer: 2.1 - inner circular layer, 2.2 - outer longitudinal layer; 3 - serous membrane: 3.1 - loose fibrous connective tissue, 3.2 - blood vessels, 3.3 - mesothelium
Rice. 271. Fallopian tube (wall section)
Staining: hematoxylin-eosin
A - primary folds of the mucous membrane; B - secondary folds of the mucous membrane
1 - mucous membrane: 1.1 - single-layer columnar ciliated epithelium, 1.2 - lamina propria; 2 - muscular layer: 2.1 - inner circular layer, 2.2 - outer longitudinal layer; 3 - serous membrane
Rice. 272. Uterus in various phases of the menstrual cycle
1 - mucous membrane (endometrium): 1.1 - basal layer, 1.1.1 - lamina propria of the mucous membrane (endometrial stroma), 1.1.2 - bottoms of the uterine glands, 1.2 - functional layer, 1.2.1 - single-layer columnar integumentary epithelium, 1.2. 2 - lamina propria (endometrial stroma), 1.2.3 - uterine glands, 1.2.4 - secretion of the uterine glands, 1.2.5 - spiral artery; 2 - muscular layer (myometrium): 2.1 - submucosal muscular layer, 2.2 - vascular muscular layer, 2.2.1 - blood vessels (arteries and veins), 2.3 - supravascular muscular layer; 3 - serous membrane (perimetry): 3.1 - loose fibrous connective tissue, 3.2 - blood vessels, 3.3 - mesothelium
Rice. 273. Endometrium in various phases of the menstrual cycle
Staining: CHIC reaction and hematoxylin
A - proliferation phase; B - secretion phase; B - menstrual phase
1 - basal layer of the endometrium: 1.1 - lamina propria of the mucous membrane (endometrial stroma), 1.2 - bottoms of the uterine glands, 2 - functional layer of the endometrium, 2.1 - single-layer columnar integumentary epithelium, 2.2 - lamina propria (endometrial stroma), 2.3 - uterine glands, 2.4 - secretion of the uterine glands, 2.5 - spiral artery
Rice. 274. Cervix
Staining: CHIC reaction and hematoxylin
A - palm-shaped folds; B - cervical canal: B1 - external os, B2 - internal os; B - vaginal part of the cervix; G - vagina
1 - mucous membrane: 1.1 - epithelium, 1.1.1 - single-layer columnar glandular epithelium of the cervical canal, 1.1.2 - stratified squamous non-keratinizing epithelium of the vaginal part of the cervix, 1.2 - lamina propria of the mucous membrane, 1.2.1 - cervical glands; 2 - muscular layer; 3 - adventitia
The area of the “junction” of multilayered squamous non-keratinizing and single-layered columnar glandular epithelium is shown by thick arrows
Rice. 275. Placenta (general view)
Staining: hematoxylin-eosin Combined drawing
1 - amniotic membrane: 1.1 - amnion epithelium, 1.2 - amnion connective tissue; 2 - amniochorial space; 3 - fetal part: 3.1 - chorionic plate, 3.1.1 - blood vessels, 3.1.2 - connective tissue, 3.1.3 - fibrinoid, 3.2 - stem (“anchor”) chorionic villi,
3.2.1 - connective tissue (villus stroma), 3.2.2 - blood vessels, 3.2.3 - cytotrophoblast columns (peripheral cytotrophoblast), 3.3 - terminal villus, 3.3.1 - blood capillary,
3.3.2 - fetal blood; 4 - maternal part: 4.1 - decidua, 4.1.1 - loose fibrous connective tissue, 4.1.2 - decidual cells, 4.2 - connective tissue septa, 4.3 - intervillous spaces (lacunae), 4.4 - maternal blood
Rice. 276. Terminal villi of the placenta
A - early placenta; B - late (mature) placenta Staining: hematoxylin-eosin
1 - trophoblast: 1.1 - syncytiotrophoblast, 1.2 - cytotrophoblast; 2 - embryonic connective tissue of the villi; 3 - blood capillary; 4 - fetal blood; 5 - fibrinoid; 6 - mother's blood; 7 - placental barrier
Rice. 277. Mammary gland (non-lactating)
Staining: hematoxylin-eosin
1 - terminal buds (unformed terminal sections); 2 - excretory ducts; 3 - connective tissue stroma; 4 - adipose tissue
Rice. 278. Mammary gland (lactating)
Staining: hematoxylin-eosin
1 - lobule of the gland, 1.1 - terminal sections (alveoli), 1.2 - intralobular duct; 2 - interlobular connective tissue layers: 2.1 - interlobular excretory duct, 2.2 - blood vessels
Rice. 279. Mammary gland (lactating). Lobule area
Staining: hematoxylin-eosin
1 - terminal section (alveolus): 1.1 - basement membrane, 1.2 - secretory cells (galactocytes), 1.2.1 - lipid droplets in the cytoplasm, 1.2.2 - release of lipids by the mechanism of apocrine secretion, 1.3 - myoepitheliocytes; 2 - layers of loose fibrous connective tissue: 2.1 - blood vessel
Uterine(another term is fallopian) pipes- these are two very thin tubes with a lining layer of ciliated epithelium, going from the ovaries of female mammals to the uterus through the uterine-tubal anastomosis. In non-mammalian vertebrates, the equivalent structures are the oviducts.
Story
Another name for the fallopian tubes is "fallopian" in honor of their discoverer, the 16th-century Italian anatomist Gabriele Fallopio.
Video about fallopian tubes
Structure
In a woman's body, the fallopian tube allows the egg to travel from the ovary to the uterus. Its various segments (lateral, medial): the infundibulum and associated fimbriae near the ovary, the ampulla-like region which represents the main part of the lateral segment, the isthmus which is the narrower part connecting to the uterus, and the interstitial region (also known as the intramural), which crosses the musculature of the uterus. The uterine orifice is the place where it meets the abdominal cavity, while its uterine opening is the entrance to the uterine cavity, the uterine-tubal anastomosis.
Histology
In a cross-section of the organ, four separate layers can be seen: serous, subserous, lamellar propria and internal mucous layer. The serous layer originates from the visceral peritoneum. The subserous layer is formed by loose outer tissue, blood vessels, lymphatic vessels, external longitudinal and internal circular layers of smooth muscle. This layer is responsible for the peristaltic activity of the fallopian tube. The lamellar layer proper is vascular connective tissue. There are two types of cells in the simple columnar epithelium of the fallopian tube (oviduct). Ciliated cells predominate everywhere, but they are most numerous in the funnels and ampoules. Estrogen increases the production of cilia on these cells. Scattered between the ciliated cells are secretory cells that contain apical granules and produce a tubular fluid. This fluid contains nutrients for sperm, eggs and zygotes. The secretions also promote sperm capacitation by removing glycoproteins and other molecules from the sperm plasma membrane. Progesterone increases the number of secretory cells, while estrogen increases their height and secretory activity. The tubular fluid flows against the action of the cilia, that is, towards the fimbrial end.
Due to longitudinal variation in histological features, the isthmus has a thick muscular layer and simple mucous folds, while the ampulla has complex mucous folds.
Development
Embryos have two pairs of canals to admit gametes from the body; one pair (Müllerian ducts) develops into the female fallopian tubes, uterus and vagina, while the other pair (Wolffian ducts) develops into the male epididymis and vas deferens.
Typically, only one pair of these canals will develop, while the other regresses and disappears in the womb.
The homologous organ in men is the vestigial appendix testis.
Function of the fallopian tubes
The main function of these organs is to assist in fertilization, which occurs as follows. When an oocyte develops in the ovary, it is enclosed in a spherical collection of cells known as a follicle. Just before ovulation, the primary oocyte completes meiosis I phase to form the first polar body and the secondary oocyte, which arrests in meiosis II metaphase. This secondary oocyte is then ovulated. Rupture of the follicle and the ovarian wall allows the release of the secondary oocyte. The secondary oocyte is captured by the fimbriated end and moves into the ampulla of the fallopian tube, where, as a rule, it meets the sperm and fertilization occurs; Stage II of meiosis is completed immediately. The fertilized egg, which has now become a zygote, moves towards the uterus, facilitated by the activity of the cilia and muscles of the uterus. After about five days, the new embryo enters the uterine cavity and is implanted into the uterine wall on the 6th day.
The release of the egg does not alternate between the two ovaries and appears to be random. If one of the ovaries is removed, the remaining one produces an egg every month.
Sometimes the embryo implants in the fallopian tube instead of the uterus, creating an ectopic pregnancy, commonly known as a “tubal pregnancy.”
Clinical significance
Although a complete test of tubal function is not possible in infertile patients, tubal patency testing is important since tubal obstruction is a major cause of infertility. Hysterosalpingography, dye laparoscopy, or contrast hysterosalpingosonography will demonstrate that the tubes are open. Blowing pipes is a standard procedure for patency testing. During surgery, their condition can be checked by injecting a dye, such as methylene blue, into the uterine cavity and seeing it pass through the tubes when the cervix is blocked. Because tubal disease is often associated with chlamydial infection, testing for antibodies to Chlamydia has become a cost-effective form of screening for pathologies of these organs.
Inflammation
Salpingitis is a disease of the fallopian tubes accompanied by inflammation, which can occur independently or be part of an inflammatory disease of the pelvic organs. Saccular expansion of the fallopian tube in its narrow part, due to inflammation, is known as adenosalpingitis. Like pelvic inflammatory disease and endometriosis, it can lead to obstruction of these organs. Obstruction is associated with infertility and ectopic pregnancy.
Fallopian tube cancer, which usually develops in the epithelial lining of the fallopian tube, has historically been considered a very rare malignancy. Recent evidence suggests that it is likely to be largely what was classified in the past as ovarian cancer. While this problem may be misdiagnosed as ovarian cancer, it is not particularly significant since ovarian and fallopian tube cancers are treated in the same way.
Surgery
A salpingectomy is an operation to remove the fallopian tube. If removal occurs on both sides, it is called a bilateral salpingectomy. An operation that combines the removal of an organ with the removal of at least one ovary is called a salpingo-oophorectomy. Surgery to correct the obstruction is called a fallopian tubeplasty.
To determine the cause of an ectopic or frozen pregnancy, doctors may order a histology analysis. Using this method, it is possible to find out why abnormalities occur in the body.
Very often, to make a more accurate diagnosis in gynecology, the doctor refers the patient to a histology analysis. It is in this medical field that such research helps in determining an accurate diagnosis and the causes of the disease or pathology. There are certain indications for which the doctor refers for histology, for example, after curettage of a frozen pregnancy. The most popular reasons for analysis are:
- To detect the presence of an inflammatory process, a malignant tumor;
- Interrupted or frozen pregnancy;
- Determination of the nature of the neoplasm: cysts, polyps, papillomas;
- After curettage of the uterine cavity;
- Determining the cause of female infertility;
- Study of cervical pathologies and other indications.
Decoding the result of histology in gynecology
If you donated tissue samples for testing at a public hospital, you will hear the results at your doctor's office. If you take the test in a private clinic, the conclusion will be given to you. But you won’t be able to decipher the histology on your own, and it doesn’t matter whether the study was done after a frozen pregnancy or for other indications. On the form you can read your data, which drugs were used for the analysis, and below the results themselves will be indicated in Latin. The report will indicate not only the malignant cells detected, but also all the tissues identified. Depending on the indication for histological examination, different data will be indicated. For example, the histology results after a frozen pregnancy or after examination of the uterus due to infertility will additionally indicate the cause of this pathology. Only a medical specialist can decipher the conclusion. He will also give the necessary recommendations for subsequent treatment.
Histology of frozen pregnancy
Pregnancy does not always end favorably. There are reasons why pregnancy is terminated. Frozen pregnancy has recently become a popular phenomenon. The fetus stops developing, but a miscarriage may not occur until certain moments. To understand the reason, a histology analysis is performed after a frozen pregnancy. This procedure is done to identify the cause of an unpleasant pathology immediately after cleaning the uterine cavity. Tissue from a dead embryo is examined, but in some cases, specialists may take uterine epithelium or fallopian tube tissue for analysis. Histology of the fetus after a frozen pregnancy will be able to show the real cause of the pathology, which can be eliminated with the help of medications.
Histology of ovarian cyst
There are many diseases in gynecology that can lead to serious complications, including infertility. In some cases, an ovarian cyst develops asymptomatically and can be detected either during a random examination or when severe symptoms appear. Cyst removal can be done using different methods, but laparoscopy is most often used. After removal of the tumor, it is sent for histological examination. The results of histology of an ovarian cyst are usually ready in 2-3 weeks. They will allow you to find out the nature of the formation, whether it was malignant, and the doctor will prescribe the necessary treatment.
Histology of ectopic pregnancy
Ovulation of an egg can occur not only in the uterus, but also in the fallopian tube. In this case, the probability of fetal development and a favorable pregnancy outcome is zero. If an ectopic pregnancy is detected, specialists perform a special procedure called laparoscopy. All excess is removed from the fallopian tube and tissue samples are taken for histological examination. Histology after an ectopic pregnancy will be able to determine the cause of the development of the pathology. Most often, the results show that an inflammatory process has occurred in the fallopian tubes. But there are other causes of ectopic pregnancy that histological examination can reveal.
The fallopian tubes (oviducts, Fallopian tubes) are paired organs through which the egg passes from the ovaries to the uterus.
Development. The fallopian tubes develop from the upper part of the paramesonephric ducts (Müllerian canals).
Structure. The wall of the oviduct has three membranes: mucous, muscular and serous. The mucous membrane is collected in large branched longitudinal folds. It is covered with a single-layer prismatic epithelium, which consists of two types of cells - ciliated and glandular, secreting mucus. The lamina propria of the mucous membrane is composed of loose fibrous connective tissue. The muscular layer consists of an internal circular or spiral layer and an external longitudinal one. On the outside, the oviducts are covered with a serous membrane.
The distal end of the oviduct expands into a funnel and ends with a fimbriae (fimbriae). At the time of ovulation, the vessels of the fimbriae increase in volume and the funnel tightly covers the ovary. The movement of the germ cell along the oviduct is ensured not only by the movement of the cilia of the epithelial cells lining the cavity of the fallopian tube, but also by peristaltic contractions of its muscular membrane.
Uterus
The uterus (uterus) is a muscular organ designed to carry out the intrauterine development of the fetus.
Development. The uterus and vagina develop in the embryo from the distal portion of the left and right paramesonephric ducts at their confluence. In this regard, at first the body of the uterus is characterized by some bicornuity, but by the 4th month of intrauterine development the fusion ends and the uterus acquires a pear-shaped shape.
Structure. The wall of the uterus consists of three membranes:
mucous membrane - endometrium;
muscular membrane - myometrium;
serous membrane - perimetry.
The endometrium has two layers - basal and functional. The structure of the functional (superficial) layer depends on ovarian hormones and undergoes deep restructuring throughout the menstrual cycle. The mucous membrane of the uterus is lined with single-layer prismatic epithelium. As in the fallopian tubes, ciliated and glandular epithelial cells are secreted here. Ciliated cells are located mainly around the mouths of the uterine glands. The lamina propria of the uterine mucosa is formed by loose fibrous connective tissue.
Some connective tissue cells develop into special decidual cells that are large in size and round in shape. Decidual cells contain lumps of glycogen and lipoprotein inclusions in their cytoplasm. The number of decidual cells increases during the formation of the placenta during pregnancy.
The mucous membrane contains numerous uterine glands, extending through the entire thickness of the endometrium and even penetrating into the superficial layers of the myometrium. The shape of the uterine glands is simple tubular.
The second lining of the uterus - the myometrium - consists of three layers of smooth muscle cells - the internal submucosal layer (stratum submucosum), the middle vascular layer with an oblique longitudinal arrangement of myocytes (stratum vasculosum), rich in vessels, and the external supravascular layer (stratum supravasculosum) also with an oblique longitudinal arrangement of muscle cells, but cross in relation to to the vascular layer. This arrangement of muscle bundles has a certain significance in regulating the intensity of blood circulation during the menstrual cycle.
Between the bundles of muscle cells there are layers of connective tissue replete with elastic fibers. Smooth muscle cells of the myometrium, about 50 microns in length, greatly hypertrophy during pregnancy, sometimes reaching a length of 500 microns. They branch slightly and are connected by processes into a network.
The perimeter covers most of the surface of the uterus. Only the anterior and lateral surfaces of the supravaginal part of the cervix are not covered by peritoneum. The mesothelium lying on the surface of the organ and loose fibrous connective tissue, which make up the layer adjacent to the muscular lining of the uterus, take part in the formation of perimetry. However, this layer is not the same in all places. Around the cervix, especially on the sides and front, there is a large accumulation of adipose tissue, which is called pyrometry. In other parts of the uterus, this part of the perimeter is formed by a relatively thin layer of loose fibrous connective tissue.
Cervix (cervixuteri)
The mucous membrane of the cervix is covered, like the vagina, with stratified squamous epithelium. The cervical canal is lined with prismatic epithelium, which secretes mucus. However, the largest amount of secretion is produced by numerous relatively large branched glands located in the stroma of the folds of the mucous membrane of the cervical canal. The muscular layer of the cervix is represented by a thick circular layer of smooth muscle cells, which makes up the so-called uterine sphincter, during the contraction of which the mucus is squeezed out of the cervical glands. When this muscle ring relaxes, only a kind of aspiration (suction) occurs, facilitating the retraction of sperm that has entered the vagina into the uterus.
Features of blood supply and innervation
Vascularization. The uterine blood supply system is well developed. The arteries that carry blood to the myometrium and endometrium are spirally twisted in the circular layer of the myometrium, which contributes to their automatic compression during contraction of the uterus. This feature becomes especially important during childbirth, since the possibility of severe uterine bleeding due to separation of the placenta is prevented.
Entering the endometrium, the afferent arteries give rise to small arteries of two types, some of them, straight, do not extend beyond the basal layer of the endometrium, while others, spiral, supply blood to the functional layer of the endometrium.
Lymphatic vessels in the endometrium form a deep network, which, through the lymphatic vessels of the myometrium, connects to the external network located in the perimetry.
Innervation. The uterus receives nerve fibers, mainly sympathetic, from the hypogastric plexus. On the surface of the uterus in the perimetry, these sympathetic fibers form a well-developed uterine plexus. From this superficial plexus branch branches supply the myometrium and penetrate the endometrium. Near the cervix in the surrounding tissue there is a group of large ganglia, in which, in addition to sympathetic nerve cells, there are chromaffin cells. There are no ganglion cells in the thickness of the myometrium. Recently, evidence has been obtained indicating that the uterus is innervated by both sympathetic and some parasympathetic fibers. At the same time, a large number of receptor nerve endings of various structures were found in the endometrium, the irritation of which not only causes changes in the functional state of the uterus itself, but also affects many general functions of the body: blood pressure, respiration, general metabolism, hormone-forming activity of the pituitary gland and others endocrine glands, and finally, on the activity of the central nervous system, in particular the hypothalamus.
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