Female Reproductive System: Anatomy, Genitalia, Ligaments, and Blood Supply, Exercises of Gynecology

Download Female Reproductive System: Anatomy, Genitalia, Ligaments, and Blood Supply and more Exercises Gynecology in PDF only on Docsity! The female genitals are divided into external and internal. Internal organs, unlike external ones, are not available for visual inspection without application of special techniques of obstetric and gynecological examination. External genitalia (genitalia externa) include: pubis, large and small lips of pudendum, clitoris, vestibule of the vagina, large glands of the vestibule of the vagina, hymen, perineum. Pubis ( mons pubis) is a triangular area situated in the the lowest part of the anterior abdominal wall, has a significantly developed subcutaneous adipose tissue. With the beginning of puberty the pubic surface gets covered with hair. The upper border of hair distribution, which is horizontal in women, is the border of the pubis from above, the lateral borders of pubis are inguinal folds. Girls who have not reached puberty have no pubic hair, in older women, pubic hair decreases after termination of menstruations.This hair growth is associated with ovarian function. Large lips of pudendum (labia pudenda majora) are two skin folds that starts from the pubis, where they form an anterior labial commissure. Length of each is 8 cm and 2-3 cm wide. At the perineum they come into the posterior labial commissure (commissura posterior). The skin of the large lips of pudendum is covered with hair and contains sweat and sebaceous glands, subcutaneous adipose tissue is well developed. In the lower third of the thickness of the large lips of pudendum are situated Bartholin’s glands (glandulae Bartolini). They have an alveolar-tubular structure and excretory ducts which open in the vaginal orifice at the internal surface of the small lips of pudendum. Bartholin’s glands produce a transparent alkaline secret. Small lips of pudendum (labia pudenda minora) are two skin folds, covered with large lips of pudendum. At the front they form the prepuce of clitoris, at the back they get smaller and thinner and come to the internal surface of the large lips of pudendum. They are rich in sebaceous glands, hair and sweat glands are absent. Clitoris (clitoridis) is formed by two cavernous bodies and covered on top by sensitive skin that contains large amount of sebaceous glands. It also has numerous vessels and nerves, and its skin contains a lot of nerve endings. The sebaceous glands of the clitoris secrete smegma. Functionally the clitoris is an organ of sexual sensation, when aroused, the cavernous bodies are filled with blood that causes an erection of the clitoris. Vestibule of vagina (vestibulum vaginae) is a space which borders are formed by the clitoris at the front, by the posterior labial commissure at the back, by the internal surface of the small lips of pudendum at the sides. At the top and side it borders with the virginal membrane. In the vestibule of vagina opens an external urethral orifice, the output ducts of the large glands of the vestibule, in the lateral divisions of the vestibule cavernous bodies of vestibule bulbs are situated. Large glands of the vestibule are complex tubular glands 1x0.8 cm, their excretory ducts open at the confluence of large and small lips of pudendum, in the furrow of the hymen. The glands secrete a liquid secret that moisturizes the vestibule of the vagina. Virginal membrane (hymen) is a connective tissue membrane that closes the vagina entrance. It is covered with stratified squamous epithelium. At its base are muscle elements, elastic fibers, blood vessels and nerves. It has one or several openings, or may be solid (without openings) in rare cases. Depending on its shape and location, the hymen may look like rings, crescents, prongs. During the first sexual act the hymen is ruined, which is accompanied by bleeding. In some cases the hymen stretches well and does not ruin during sexual intercourse. After its rupture stay the hymenal papillae. The area between the posterior edge of the hymen and posterior labial commissure is called navicular fossa. The hymen forms the border between external and internal genitals. Perineum (perineum) is the myofasciocutaneous plate between the posterior commissure of the large lips of pudendum and anal orifice (anterior perineum) and between the anal orifice and the apex of coccyx (posterior perineum). The thick layer of the perineum comprises muscles and their fasciae which form the pelvic floor. On The outer layer is the visceral leaf of the peritoneum, which is differently fused with the uterus in its different parts. At the front, at the point of transition to the urinary bladder, peritoneum forms a vesico-uterine fold. At the back peritoneum covers the body, the cervix, the vaginal fornix and passes to the rectum -forms a rectal-uterine recess (Douglas space). The normal position of the uterus is considered to be its forward tilt with the formation between body and cervix of the obtuse angle (anteflexio-versio). Uterine adnexa include the fallopian tubes, the ovaries. Fallopian tubes (tubae uterinae) extend from the fundus of the uterus in the area of its corners and go in the direction of upper parts of broad ligaments to the lateral walls of the pelvis. These are tubular formations that connect the uterine cavity with the abdominal cavity, through which the egg enters the uterus. Their length is 10-12 cm. There are 4 parts fallopian tube: interstitial, isthmical, ampullary, and infundibular. The width of the lumen of the interstitial part is about 1 mm, in ampullary part measures 6-8 mm. The walls of the fallopian tube consist of three layers: mucosa, muscle layer and serous (peritoneal) cover. The mucosa forms longitudinal folds covered with a single-layer columnar ciliated epithelium, its cilia move in the direction of the uterus. Between the cells of the ciliated epithelium there are secretory cells that produce secret in the tube cavity during the second phase of the menstrual cycle. The muscle layer consists of the outer layer and inner (which are longitudinal), and middle (circular) layers. Peritoneum covers the fallopian tube at the top and sides. The lower part of it is adjacent to parametral adipose tissue, through it the vessels and nerves pass. The fallopian tubes contract peristaltically, which along with the movements of the cilia promotes the promotion of the ova into the uterine cavity. Ovary (ovarium) is a paired female sex gland, its weight is 5-8 g, the length is 3-4 cm, the width is 2 cm, and the thickness is 1 cm. It produces sexual hormones such as estrogens, progesterone, and androgens. It is situated on the posterior leaf of the broad ligament of the uterus so that its smaller portion (the hilum) through which blood vessels and nerves pass, is covered by the broad ligament of the uterus, and major part is not covered by peritoneum and is located in the abdominal cavity. In the ovary, there is an epithelium that covers the free surface; albuginea; cortical and medullary substances. The ovary is covered with a cubical or low- cylindrical epithelium, during intrauterine development and early childhood is involved in the formation of primary follicles. Albuginea consists of connective tissue, its fibers have parallel to the surface of the ovary direction. The cortical layer contains numerous primary follicles, follicles in different stages of development, corpus luteus and their remains. The medullary layer of the ovary consists of a connective tissue stroma with admixtures of muscle fibers, which contains a large number of vessels and nerves. In the ovary, the growth and development of the ova occurs, which during the ovulation exits from the ruptured follicle into the abdominal cavity, and then goes by the fallopian tube into the uterine cavity. At the site of the ruptured follicle, corpus luteum is formed, it produces progesterone. To the pelvic walls, the ovary is attached by ligaments that hang it. In their thickness the vessels of the gland pass. The ovary joins with the uterus by ovarian ligaments (lig ovarii proprium). The retention of topographic correlation of the internal reproductive organs is rendered by a suspensory, fixating and supportive apparatus.The peculiarity of their function is that besides supporting the uterus and adnexa in a certain position, they provide their mobility within significant limits. The suspensory apparatus of the uterus consist of: 1) Round ligament (lig. rotundum) - a rope 10-15 cm long, 3-5 mm in diameter, which consists of smooth muscle and connective tissue. Round ligaments begin anteriorly and downwards from the tubal corners of the uterus and go under the anterior leaves of the broad ligaments through the inguinal canal, scatter on the thickness of the large lips of pudendum. 2) Broad ligament (lig. latum uteri) - transverse fold of the peritoneum, which covers corpus of the uterus and fallopian tubes, makes up their serous cover. Broad ligaments go to the lateral walls of the pelvis, where they pass into the parietal peritoneum. To their posterior surface in the lateral sections the ovaries are attached. 3) Suspending ovarian ligament or infundibulopelvic ligament (lig. suspensorium ovarii, infundibulopelvicum) - the outer part of the broad ligaments that goes from the ovary and ampullary part of the fallopian tube to the lateral wall of the pelvis. Strength of this ligament is explained by the fact that through it the vessels (the ovarian artery and vein) pass. 4) Ovarian ligaments (lig. ovarii proprium) stretch from the medial poles of the ovary to the uterus in the thickness of the posterior leaf of broad ligament. The presence of smooth muscles and branches of uterine arteries and veins that pass through it determine its strength. The fixating apparatus of the uterus consist of: 1) Main (cardinal) ligament (lig. cardinale) - consists of a grid of radially situated smooth muscles and connective tissue elements, surrounding the cervix at the level of the internal orifice. Its fibers are intertwined in the thickness of the pelvic fascia, fixing the uterus to the pelvic floor. 2) Pubovesical ligaments (lig. pubovesical) – smooth muscles and connective tissue fibers that run from the lower portion of the anterior surface of the uterus to the bladder and pubis; 3) Sacrouterine ligaments (lig. sacro-uterinum) – smooth muscles and fibrous fibers that go from the posterior surface of the cervix are slightly lower than the level of its internal orifice, cover the sides of the rectum and merge with pelvic fascia on the internal surface of the sacrum. Suspensory and fixating ligaments of the uterus during pregnancy are stretched, this ensures the mobility of the uterus within certain limits necessary for its growth.The supportive apparatus of the internal reproductive organs of a woman is the muscles and fascia of the perineum, which form the pelvic floor. Pelvic floor muscles are divided into three layers: outer, middle, and inner. The outer layer includes: 1) ischiocavernous muscle is paired, goes from the ischial tuberosity to the clitoris; is formed. The primary gonad is indifferent in structure and consists of coelomic epithelial cells (cortical layer), mesenchyma and germ cells (gonocytes) migrating to the gonad via amoeboid movements (medullar layer) from the base of the yolk sac. Migration ends by 6-7 weeks of embryonic development, so the indifferent stage of gonad development ends. Sexual differentiation is induced by sex chromosomes received in the ova in the process of fertilization. Factor, the H-Y gene, which is located in the short arm of the Y chromosome determines the development of the testicle. In week 7 embryonic development under the influence of the H-Y gene indifferent gonad turns into testicles. The gonocytes are contained in the upper (medullar) layer, which develops seminiferous cords containing germ cells primordially, they are formed from the spermatogonia, and subsequently the spermatozoa. In the embryonic testicles form sartoli cells from the coelomic epithelium and Leydig cells - from the mesenchymal tissue between the tubules. The steroid hormones synthesis begins at the 8th week of the embryonic development period. A protein polypeptide is formed in Sartoli cells and is anti-Mullerian factor. The last two components are important in differentiation of sexual characteristics. Internal genitals are formed from mesonephral (Wolf) organs paramesonephral (Muller) ducts that are laid in the embryo with a length of 15-16 mm. Paramesonephric ducts are formed of the epithelium of the urogenital fold, metanephrine – from tubules of the primary kidneys. When the embryo is 30 mm long, the genital ducts reach urogenital sinus and this completes the indifferent stage of their development. Under the influence of anti-Mullerian factor paramesonephral duct degenerates and remains as a vestige for up to 12 weeks (utriculus prostaticus and Morganeve’s hydatid). From mesonephric ducts seminal vesicles and ductus deferens are formed. The external genitals also go through an indifferent stage staring from 8 weeks of differentiation. At 18-20 weeks the formation of the external genitalia of male type is completed. The presence of two X chromosomes determines the development of the ovary (gene is located in the long arm of the X chromosome). Internal genitals (fallopian tubes, body and cervix, upper third of the vagina) are formed starting from 5- 6 weeks of pregnancy from the paramesonephral ducts. Its formation process ends at 18 weeks of intrauterine development. From the upper third of paramesonephric ducts the fallopian tube, the middle part - the body of the uterus and cervix are formed. Development of the uterus begins at 13-14 weeks intrauterine development. First the uterus is two-horned, then it acquires a saddle-shaped configuration that is often retained until birth. The formation of the cervix begins at 16-20 weeks of fetal development. Up to 33 weeks the cervix is ¾ of the total length of the uterus, by 40 weeks it becomes 2/3 of the total length of the uterus. The lower parts of the merged paramesonephric moves reach urogenital sinus and form the vagina. External genitals from 4 to 7 weeks have an indifferent character. From the 17th week, the rapid development of the labia begins from the labiosacral folds. The formation of the genitals goes through an indifferent stage. If the first stage (gonadal development) is determined genetically, then the development of male genitals is determined by secreted factors of testicles of the fetus. The ovary is capable of steroidogenesis in the antenatal period significantly less than the testicle. Ovarian hormones don’t have a decisive influence on the process of antenatal sexual differentiation. In the presence of agenesis or dysgenesis of the gonads, the genitals (internal and external) develop in the female type regardless of the set of chromosomes. In various forms of true hermaphroditism, the structure of internal and external genitalia depends on the presence of a hormone-active testosterone secreting tissue and testicular elements in the gonad of mixed type. The hypothalamic-pituitary system is laid at 4-5 weeks. Secretory activity of the adenohypophysis (FSH, LH, ACTH ) starts from 8-9weeks of pregnancy, PRL-from 19 weeks of pregnancy. Newborn period is morphological and functional state of reproductive system within 28 days after birth. During this period in the genitals and mammary glands of the newborn are shown signs of estrogenic effect: the vaginal epithelium consists of 30-40 layers and contains cells with a relatively high karyopicnotic index (up to 30%). pH of the vaginal content is acidic, lactobacilli are dominated. The ovaries and uterus are located in the abdominal cavity, the uterus is up to 3 cm long, the ratio of the length of the cervix to the body is 3:1, the angle between them is not expressed. Weight of the uterus in 4 g. Proliferative and sometimes secretory changes are observed in the endometrium. Approximately 3% of newborns when endometrial desquamation occurs, may have creamy discharge from the vagina. After birth, the level of maternal estrogens in the body the newborn falls, which stimulates the release of FSH and LH by the adenohypophysis and short-term increase in a hormonal function of the ovaries. Related to this and short-term stimulation of prolactin occurs, leading to swelling of the mammary glands and even the release of colostrum from the nipples. Up to 28 days life all manifestations of estrogenic effects disappear. Period of childhood lasts from the end of the neonatal period to 7-8 years. The adenohypophysis and ovaries complete their morphological development and are active endocrine glands. In the hypothalamus, gonadotropin-releasing hormone is produced in small amounts, but is released sporadically; slight secretion of neurotransmitters; FSH, LH are formed in the pituitary gland; maturation of the negative feedback mechanism; low secretion of estradiol, maturation of follicles to antral occurs rarely, unsystematically. The hypothalamic-pituitary-ovarian system is immature: high sensitivity of the adenohypophysis and neutrosecretory nuclei of the hypothalamus to estradiol secreted in the ovary. Puberty - age limits from 7-8 years to 17 years. The reproductive system matures and the physical development of the female body is completed. At 7-9 years (prepubertal period): in the hypothalamus synoptic connections between neurosecretory neurons are poorly developed; episodic nature of gonadotropin-releasing hormone formation; acyclic nature of LH and FSH secretion; low estrogen secretion. At 10-13 years (the first phase of puberty): secretion of gonadotropin-releasing hormone with daily cyclicity; close synaptic connections; increases the release of gonadotropins. Achieving high levels of estradiol is a signal of a powerful release of Venue: classroom, women's clinic, gynecology department. Equipment: multimedia, tables, models, photos, atlases. VIІІ Control questions 1) What applies to the external female genitals? 2) Anatomical structure and function of labia majora and minora. 3) Anatomy of the perineum and its functions in obstetric and gynecological practice. 4) What applies to the internal female genitals? 5) What parts of the uterus do you know? 6) The structure of the fallopian tubes. 7) What do you know about an ovarian function? 8) What ligaments are related to the uterine suspensive apparatus? 9) What ligaments are related to the fixating apparatus of the uterus? 10) What is the structure of the supportive apparatus? 11) Blood supply of the woman’s internal genitals. 12) Blood supply of the woman’s external genitals. 13) What are the features of the intrauterine period of reproductive sustem development? 14) What are the features of the newborn period? 15) Describe the state of the reproductive system in childhood. 16) What are the features of the hypothalamic-pituitary system of the period of maturation? 17) What are the features of the period of maturity of the reproductive system? 18) What are the features of the menopausal period? Tasks for an independent work of students 1. Work with educational literature on anatomy and histology of female reproductive organs. 2. Physiology of female genitals. IХ. Situational tasks 1. Patient, 23 years old. Menses from 13 years, 5-6 days, 28 days, moderate, painless. The last menstruation ended 5 days ago. The external genitalia are properly developed, the growth of pubic hair on the female type. When examining the cervix in mirrors, the cervix is conical, pink, the outer eye is round. The uterus is in the anteflexio position, not enlarged in size, mobile, painless. The vaults are deep, the appendages are not palpable. Parameters are free. What about the external and internal female genitals? Did a woman give birth through the natural birth canal? 2. At patient K., 38 years old, during half a year menstruations are plentiful, last on 7 days. History: uterine leiomyoma at 8 weeks of pregnancy. The walls of the uterine cavity were scraped. Histological examination revealed endometrial hyperplasia. Which hormone caused pathological changes in the endometrium? What is the histological and anatomical structure of the uterus? 3. The woman went to the women's clinic with complaints of "hot flashes", sweating, irritability, dry skin. Absence of a menstrual cycle within 8 months. In the study, the cervix is cylindrical, the outer eye is slit-like, closed. The uterus is normal in size, mobile, painless. The vaults are deep, the appendages are not palpable. Parameters are free. Mucous secretions. To what age period according to anatomical and physiological features does this patient belong? Did a woman give birth through the natural birth canal? Х. Tests 1. The external genitalia include: A. Pubis, labia majora and labia minora, clitoris, vagina, urethra. B. Pubis, labia majora and labia minora, clitoris, vaginal dorsum, bartholin glands. C. Vagina, uterus, fallopian tubes, ovaries. D. Vagina, vaginal dorsum, clitoris, labia. E. Pubis, labia, uterus, ovaries. 2. The internal genitals include: A. Uterus, ovaries, fallopian tubes, vaginal dorsum. B. Uterus, ovaries, fallopian tubes, clitoris, labia. C. Uterus, ovaries, fallopian tubes, vagina. D. Uterus, ovaries, vagina, fallopian tubes, clitoris. E. Uterus, labia minora, vagina, ovaries, fallopian tubes. 3. The boundary between external and internal genitals is: A. The dorsum of the vagina. B. The hymen. C. Small labia. D. Large labia. E. Perineum. 4. The labia majora, joining backwards, form: A. The dorsum of the vagina. B. Anterior adhesion. C. The genital slit. D. Posterior adhesion. E. The hymen. 5. How many vaults are there in the vagina? A. 2. B. 3. C. 5. D. 4. E. 1. 6. The uterus consists of: A. Body, cervix, isthmus. B. The body. C. Body, cervix. D. Body, isthmus. E. Cervix, isthmus. 7. In the fallopian tube there are: A. Interstitial part, cervical, ampullary with the neck. B. Cervical and ampullary parts. C. Interstitial and ampullary parts. D. Cervical and ampullary parts. E. Ampullary part with cervix.