CHAPTER 2 Physiology of the female genital system

1. CHAPTER 2 Physiology of the female genital system • Sec.1 physiologic characteristics in different stages • Sec.2 menstruation and its manifestation • Sec.3 ovarian cycle • Sec.4 cyclical changes of endometrium and other genital organs • Sec.5 endocrine mechanism • Sec.6 other glands of endocrine sys.

2. Section 1 Physiologic characteristics of female in different stages • （一）neonatal period：<4w • （二）childhood：4w→10y • （三）adolescence • 1． General development • 2． Genital development • 3． The 2nd sexuality • 4． menarche

3. （四）sexual maturity：≥18y sex-hormone secretion;periodic ovulation （五）climacteric period：45y→52y, oligomenorrhea→menopause Def：interval from the decline of ovarian function and the atrophy of genital organs to the cease of genital function . （六）senility：the further decline of ovarian function . manifestation：cholesterol↑，muscular atrophy，decalcification，concentric deposit of fat.

4. Section 2 Menstruation and its manifestation • 1． menstruation：regular，periodic bleeding of uterus.one of the external mark of genital maturity. • 2． menarche：the first menstruation，13-15y • 3． Menstrual cycle：the interval between two successive menstruation onset，28-30d. • 4． Duration and amount of the flow：2-7d，30-80ml • 5． About menstrual blood：dark-red，partially hemolyzed blood with mucus and cellular debris • 6.CM.during menstrual cycle:pelvic discomfort

5. Section 3 Ovarian cycle • （一） function • ① genital→periodic ovulation • ② endocrine→sex-hormone secretion • （二）cyclical changes • 1. Development and maturation of follicle • ① primitive follicle：oogonium surrounded by spindle or flat cells • ② developing follicle：spindle cells→granulosa cells;interstitial cells→theca folliculi cells • ③ mature follicle：theca folliculi externa/interna,granulosa cells，follicle cavity，cumulus oophorus,zone pellucida,radiate zone,ovum

6. 2．Ovulation:mem.ruptured,ovum released 3．corpus luteum：ovulation→corpus rubrum→mature corpus luteum（granulosa-corpus luteum cells，theca-corpus luteum cells） 4.decline of corpus luteum：12-16d→8-10w→corpus albicans (三)sex hormone:estrogen is produced by theca folliculi cells and granulosa cells before ovulation;estrogen and progesterone is produced by corpus luteum. 1.physiologic action of estrogen. (1)the second sexuality’s appearance.

7. (2)action on external genital organs hypertrophy of uterus,fallopian tubes and lower genital tract at puberty;hypertrophy and increased vascularity in pregnancy. Controlling the monthly proliferative phases of the endometrium. Sensitizing uterus to the action of oxytocin. Causing vaginal epithelium to proliferate with a increase in thickness of the superficial stratified layers and a increase in their glycogen content. Cervical orifice is loosened and cervical glands secrete an abundance of mucus.

8. Increasing the motility of the fallopian tubes to help the transport of ovum from ovary to uterus. • Necessary for the development of the follicles. • (3)relation to menstruation. • estrogen↑→proliferation and vascularity of endometrium;FSH↑,LH↑↑→follicle developing and ovulation(if no pregnancy)→withdrawl in the 4th week→shrinkage of endometrium and vasoconstriction of deeper coiled aterioles→the vessels relax intermittently→menstrual bleeding • (4)action on the breasts • enlarging breasts by the proliferation of the ducts; pigmentation of nipple and areola

9. (5)action on metabolism sodium and water retention;cholesterol decrease. (6)action on the bone:Ca2+-deposit on the bones (7)hormone-feed-back action 2.physiologic action of progesterone (1)action on the internal genital organs inhibiting the sensitivity of uterus; leading to the secretary phase of endometrium; cervical orifice closed; inhibiting the motility of the tubes; causing the desquamation of vaginal epithelium. (2)action on breasts causing the development of the acinus

10. (3)feed-back action:negative (4)action of temperature-rising on Hypothalamus (5)Action on metabolism causing Na+ and water excreted

11. Sec.4 cyclical changes of endometrium and other genital organs • (一)endometrial cycle • 1.proliferative phase:soon after menstruation,the low cuboidal surface epithelium covers the denuded area under the influence of estrogen the cells of the surface and glandular epithelium become taller and more columner,the glands elongated,widened and more tortuous.

12. 2.secretory phase:although the surface epithelium remains unaltered from that of the proliferative phase ,the cells of the glandular epithelium show specific changes(the glands more tortuous and twisted,the hypertrophy of stroma cells continues,the arterioles growing spirally into the functional layer become more coiled.) 3.menstrual phase:toward the end of the cycle ,E2 and P ↓→rapid decrease in the thickness of endometrium due to a diminished blood-supply,in the ischaemic functional zone metabolites↑and cause the coiled vessels in functional layer to contract →bleeding through their necrotic walls with desquamation following the necrosis of the functional layer →an

13. Intrauterine coagulum which is subsequently dissolved by thrombolysin and discharged as menstrual fluid. (二)cyclical changes of other sites of genital tract. 1.vaginal epithelium (1)before ovulation:estrogen↑→hypertrophy of basal cells and thickness of epithelium↑ (2)after ovulation: progesterone↑ →desquamation of epithelial cells. 2.cervical mucus. (1)before ovulation:estrogen↑→amount↑,thin and translucent,liable to wiredrawing,fern-like crystals in mucous smear. 1. 阴道粘膜的周期性变化. 2. 宫颈粘液的周期性变化 3. 输卵管的周期性变化. 第五节下丘脑-垂体-卵巢轴的相互关系

14. (2)After ovulation:progesterone↑→amount↓, thick and turbid,ellipsoid in mucus smear. Sec.5 the H-P-O axis in the menstrual cycle

15. hypothalamus pituitary ovary uterrus Feed-back mechanism

16. Endometrial cycle

17. Vaginal epithelium

18. Primitive follicle

19. Mature follicle

20. Corpus luteum

21. Corpus-luteum formation ovulation