Female Reproductive Physiology

1. Female Reproductive Physiology

2. Ovaries

3. Physiologic Anatomy of the Female Sexual Organs

4. Ovaries and Fallopian Tubes

5. Physiologic Anatomy of the Female Sexual Organs

6. Female Hormonal System • Gonadotropin Releasing Hormone (GnRH): Hypothalamus • Luteinising Hormone (LH): Anterior Pituitary (Gonadotrophic cells) • Follicle Stimulating Hormone (FSH): Anterior Pituitary (Gonadotrophic cells) • Estrogen: Ovaries (Theca interna) • Progesterone: Ovaries (Corpus luteum)

7. Monthly Ovarian Cycle (Menstruel Cycle) • Duration of the cycle averages 28 days • It may be as short as 20 days or as long as 45 days in some women, although abnormal cycle length is frequently associated with decreased fertility. Puberty • Effects of gonadotrophic hormones (LH and FSH) on ovaries • Onset of puberty (11-15) • The first menstruel cycle is called menarche.

8. Development of Ovarian Follicles • When a female child is born, each ovum in their ovaries is called primordial follicle (surrounded by one layer of granulosa cells) • There are thousands of primordial follicles (about 400.000) and their number declines during the course of sexual life • Granulosa cells provide the necessary nutrition for the primordial cells • Oocyte maturation intibiting factor suppresses the activity of ovum to stay as promordial follicle state

9. Development of Ovarian Follicles

10. Follicular growth and development

11. Oogenesis

12. Follicular development • With each menstrual cycle, 6 to 12 primordial follicles start growing under the influence of FSH and LH • In each cycle, just one follicle becomes mature and the remaining ones undergo atresia • The main hormone to trigger development of follicles is FSH, however, synergistic effect of LH is also necessary • LH plays the primary role in the induction of ovulation

13. Ovarian Follicle

14. Ovulation

15. Two Phases of Menstrual Cycle • Follicular phase • Luteal phase • Corpus luteum • Luteinizing effect of LH • Secretions of corpus luteum: Progesteron and estrogen • Regression of corpus luteum and start of a new menstrual cycle

16. Ovulation and Body Temperature

17. Development of Ovarian Follicles

18. Theca interna and Synthesis of Estrogen Theca interna Theca externa • Ovulation: • Role of proteolytic enzymes • Increased vasculatisation • Prostaglandins

19. Ovarian Follicular Development

20. Hormonal Changes During Menstrual Cycle

21. Pulsatile Release of Hormones

22. Menstrual cycle in women

23. Summary:

24. Ovarian Hormones • Estrogen and progesteron are bound to sex hormone binding globulin for transport • Steroid hormones are metabolized in the liver • Estradiol 17-b, Estriol ve Estrone • Receptors for steroid hormones are found in cytoplasma and (in the nucleus to some extent) • They stimulate gene transcription

25. Estrogens

26. Functions of Estrogens • Effects on uterus and female genital organs • Effects on fallopian tubes • Effects on mammary glands: develop the stromal tissue and canal systems and cause accumulation of fat in the breast tissue • Skeleton; stimulate osteoblastic activity. Osteoporosis develops in its absence in elder ages • Estrogens increase total body proteins slightly • Effects of estrogens on metabolism and fat deposition • Effects on the skin and hair distribution • Effects on the water-electrolyte balance

27. Functions of Progesterone • It starts secretory changes in the uterus • Effects on the fallopian tubes: increased secretion • Effects on the mammary tissue: proliferation of alveolar cells; and stimulates development of lobule and alveole in the breast tissue

28. Monthly Endometrial Cycle & Menstruation • Proliferative (estrojenic) phase of the endometrial cycle before ovulation • Secretory (progesteron) phase of the endometrial cycle after ovulation • Menstruation: Two days before the end of monthly menstrual cycle, corpus luteum suddenly regresses, E2 and P secretions rapidly decline. • Menstruation (Desquamation of the endometrium) is seen • Leukorrhea during menstruation

29. Monthly Endometrial Cycle & Menstruation

30. Hypotalamo-Hypophyseal-Gonadal Axis Hypothalamus GnRH + _ + A. Hypophsis LH and FSH _ + + _ Inhibin Estrogen & Progesterone Ovaries

31. Hypotalamo-Hypophyseal-Gonadal Axis

32. Puberty and Menarche • Puberty, onset of the sexual life • Rhytmical increase in GnRH release starting about the ages of 9-11 • Menarche, onset of menstrual cycles

33. Rates of secretion of gonadotropic hormones

34. Menopause • Between the ages of 40 and 50, menstrual cycle becomes irregular and mostly ovulation does not occur • The cause of menopause is the run out of ovaries (primordial follicles) • Estrogen systhesis falls below the critical levels • LH and FSH are secreted abnormally and constantly at high levels • Symptoms of menopause (Fever, irritability, anxiety, fatigue, increased fragility of the bones) • Hormone Replacement Therapy (HRT)

35. Estrogen Secretion Throughout Life

36. Secretory Abnormalities in the Ovaries • Hypogonadism • Ovarian tumors and hypersecretion • Endometriosis • Infections (Endometritis, Salphingitis) • Infertility ve sterility • Rhytmic method in contraception • Contraceptive pills

37. Structures of Oral Contraceptive Steroids • Combination pill: prevents development of ovarian follicle and ovulation by inhibiting GnRH, FSH and LH • Progestin-only pill: acts upon cervical mucus to create inhospitable environment

38. RU-486 (Mifepristone) • blocks progesterone effects at its receptor • used with misoprostol, a prostaglandin E2 (PGE2) analog that stimulates smooth muscle contraction