Female Sexual Anatomy

1. 3 Female Sexual Anatomy

2. Female Sex Organs • All embryos appear as female at first • Genetic and hormonal signals trigger the development of male organs in those embryos with XY chromosomes that will become male

3. Female Sex Organs in Utero

4. Female Sex Organs • In spite of all that is known about female sex organs, some anatomical questions remain unknown or disputed • Range in clitoral size • Existence and function of the G-spot • Placement of nerves in the pelvic cavity

5. Female Sex Organs • Sex organs serve a reproductive function • Also serve other functions: • Bringing pleasure to self • Giving pleasure to others • May serve to attract potential sexual partners • Sharing of genital sexuality can play a bonding role in relationships

6. External Structures • External female genitals: • mons pubis • clitoris • labia majora • labia minora • These genitals are collectively known as the vulva • Often referred to as “vagina,” yet the vagina is an internal structure

7. External Structures

8. Mons Pubis • Latin for “pubic mound:” • The pad of fatty tissue that covers the area of the pubic bone about 6” below navel. • Pubic hair grows on mons pubis beginning in puberty • In many women, this area is sensitive to stimulation

9. Clitoris • The Clitoris is the center of sexual arousal in the female • Contains a high concentration of nerve endings • Exquisitely sensitive to stimulation • glans clitoris: the shaft of the clitoris • Clitoral hood: covers glans when clitoris not engorged • Structurally analogous to penis, though sole function of the clitoris is sexual arousal

10. Clitoris • Clitoris also has an internal structure • Two 3.5” long branches called crura • crura contain two corpora cavernosa: hollow chambers that fill with blood and swell during arousal • The clitoris when stimulated • Enlarges initially, then retracts beneath hood just before and during orgasm • Follows same pattern with repeated orgasms, though swelling is less pronounced

11. Labia Majora and Minora • Labia Majora • Two folds of spongy flesh extending from the mons pubis and enclosing the labia minora, clitoris, urethral opening, and vaginal entrance

12. Labia Majora and Minora • Labia Minora • Small folds within the labia majora that meet above the clitoris to form the clitoral hood • They vary in appearance from woman to woman • They are sensitive to the touch and swell during sexual arousal • They enclose the “vestibule:” the vaginal opening

13. External genitals during sexual arousal • Clitoris becomes erect • Labia minora widen • Vestibule (vaginal opening) becomes visible • Bartholin’s glans (located in the vestibule) secrete small amount of moisture

14. Internal Structures • Vagina: from Latin word for sheath • Two reproductive functions: • Encompasses penis during coitus (vaginal intercourse) • Birth canal • Introitus: the lower third of the vagina • The majority of the vagina’s nerve endings are there • Hymen: named for Roman god of marriage • a thin membrane that partially covers introitus prior to first intercourse or other insertion

15. Internal Structures

16. Internal Structures • Grafenberg Spot (G-spot) • An erotically sensitive area on front wall of the vagina mid-way between pubic bone and cervix • Existence somewhat controversial • Uterus: a hollow, thick-walled muscular organ • Accommodates developing fetus during pregnancy • Only 3” by 3” in women who have not given birth • Inner lining of uterine walls known as endometrium • Cervix: the tapered end of the uterus, extends and opens into the vagina • Secretes mucous; menstrual fluid travels through

17. Internal Structures

18. Internal Structures • Ovaries:gonads that produce gametes • Produce egg cells (oocytes; ova) for reproduction • Two ovaries; size and shape of large almonds • Ovaries release oocytes in a process called ovulation • Fallopian tubes: • Also known as uterine tubes of oviducts • One tube extends toward each ovary • They fan over the ovaries, and carry oocytes into the uterus during ovulation

19. Other Structures • Urethra: tube through which urine passes • Urethral opening • Perineum: area between genitals and anus • Pelvic floor

20. Other Structures • Anus: opening of rectum • Contains two sphincters (circular muscles that open and close like valves) • Some women and men find that the tissue of the anus is erotically sensitive • The lining of the rectum is fragile • if engaging in anal sex play care must be taken not to rupture the delicate tissues

21. Other Structures • Breasts: both women and men have them • Reproductive function of female breasts is to nourish offspring through lactation • Composed of fatty tissue and 15-25 lobes that radiate around a central nipple • Areola: the ring of darkened skin around nipple • Nipples get erect in response to touch, cold, or sexual arousal • Many (not all) women find breast stimulation pleasurable.

22. Other Structures: Breasts

23. Female Sexual Physiology: Reproductive Hormones • Hormones: chemical substances that serve as messengers • Gonadotropins act directly on gonads • Estrogens: affect maturation of reproductive organs, menstruation, and pregnancy • Progesterone: helps maintain the uterine lining

24. Female Sexual Physiology: Reproductive Hormones

25. Female Sexual Physiology: Reproductive Hormones

26. Female Sexual Physiology: The Ovarian Cycle • Cycle averages 28 days • Normal women’s cycles last between 21 & 40 days • Generally occurs in only one ovary per month

27. The Ovarian Cycle

28. The Ovarian Cycle • 3 Phases: • Follicular phase: Days 1-10 • Hormones signal 10 to 20 follicles to grow on ovaries; Estrogen matures one oocyte • Ovulatory phase: Days 11-14 • Oocyte undergoes cell division; Follicle wall thins and ruptures; oocyte enters abdominal cavity near fimbrae of fallopian tube • Luteal phase: Days 14-28 • Estrogen levels drop; egg travels through fallopian tube towards uterus

29. The Ovarian Cycle: Follicular Phase

30. The Ovarian Cycle: Ovulatory Phase

31. The Ovarian Cycle: Luteal Phase

32. Menstruation

33. The Menstrual Cycle • 3 Phases: • Menstrual phase (about 3-5 days) • Endometrium is shed • Endometrial tissue, mucous, other secretions, and 2-5 oz. Blood is expelled through vagina • Proliferative phase (about 9 days) • Endometrium thickens, clear thin mucus secreted • Ends with ovulation • Secretory phase (14 days) • endometrium prepares for arrival of fertilized ovum • If no fertilization, ends with shedding of endometrium

34. Menstrual Effects • Emotional, physical, or behavioral changes • The vast majority of women notice in the week prior to menstruation • More severe symptoms are associated with Pre- Menstrual Syndrome (PMS) • Dysmenorrhea • pelvic cramping and pain during menstruation • Caused by prostaglandins, a type of hormone • Amenorrhea • absence of menstruation for reasons other than aging

35. Female Sexual Response Models • Masters & Johnson 4 Phase Model: • excitement • plateau • orgasm • resolution

36. Female Sexual Response Models • Kaplan’s Tri-Phasic Model • Desire • Excitement • Orgasm

37. Female Sexual Response Models • Loulan’s Sexual Response Model: • Incorporates biological & affective dimensions • Willingness • Desire • Excitement • Engorgement • Orgasm • Pleasure

38. Desire: Mind or Matter? • Desire is the psychological component of sexual arousal. • A complex interaction between • Thoughts and feelings • Sensory organs • Neural responses • Hormonal reactions • Occurs throughout many parts of the body

39. Women’s Sexual Excitement • Sweating: moistening of vaginal walls • Tenting: inner 2/3 of vagina expands • Labia may enlarge or flatten & separate • Clitoris swells • Breathing and heart rate increase • Nipples become erect, breasts may enlarge • Uterus elevates

40. Women’s Sexual Excitement • As excitement increases • Clitoris retracts beneath clitoral hood • Vaginal opening decreases by about 1/3 • Outer third of vagina becomes more congested, forming the orgasmic platform. • Continued stimulation brings orgasm: • Rhythmic contractions of the vagina, uterus, and pelvic muscles accompanied by pleasurable sensation.