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| Home > Reproductive Anatomy > Female Sexual and Reproductive Organs
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| | Female Sexual and Reproductive Organs
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 Perineum is the area of skin and muscle between the vagina and anus. It comprises of pelvic floor muscles, external genitalia, urethra, anus, and perineal body (the area between the vagina and anus). The vaginal opening, clitoris, labia major, labia minora, and mons pubis (the fatty tissue over the pubic bone) form the external genetalia of the female. The internal reproductive organs are two uterine or fallopian tubes or oviducts, the uterus or the womb, the vagina and two ovaries. Two fallopian tubes extend from the upper sides of the uterus toward the ovaries. The function of the uterine tubes is to convey an ovum, which is fertilized in the tube, to the uterus. The uterus is a hollow, Muscular, pear-shaped organ. It is located in the pelvis behind the bladder in front of the rectum.
The upper part of the uterus is called the body and the lower portion is called the cervix. The cervix extends into the vagina. The vagina is the tubular tract leading from the uterus to the exterior of the body thus connecting the internal and external genitalia. The source of the ova, the female germ cells, is the female gonad or ovary. They are located on either side of the uterus and are the female sex glands. The ovaries ripen and expel ova (eggs). Of the hundreds of thousands of ova present in the ovaries, only about 400 to 450 actually are expelled (ovulated) in a woman`s lifetime. Like the testes in males, the ovaries are also responsible for development of secondary sexual characteristics in females.
The ovaries produce female sex hormones estrogen and progesterone. During adolescence, along with hormones from the pituitary and adrenal glands, estrogen stimulates the development of secondary sexual characteristics in the female, such as enlarged breasts, body hair etc. The ovaries undergo monthly cyclic changes throughout the reproductive years of a woman (except when she is pregnant). This is known as the menstrual cycle. Pituitary hormones cause an ovum to mature and its follicle (the sac surrounding the ovum) to enlarge and secrete estrogen. This process then stimulates the growth of the endometrium (the lining of the uterus). In the middle of the menstrual cycle, a single ovum is released from its follicle to be carried through the oviduct into the uterus. This process is called ovulation. Another pituitary hormone causes the follicle to pro-duce progesterone, which stimulates further development of the lining of the uterus, enabling it to receive and nourish the fertilized ovum. If the ovum is not fertilized, the levels of estro-gen and progesterone decrease and the uterus sheds its redundant lining along with the unfertilized ovum. This monthly shedding process is called menstruation. Women show considerable variation in the lengths of their menstrual cycles. While cycle length may vary, 28 days is generally taken as representative of the average ovulatory cycle in women. Convention uses the onset of menstrual bleeding to mark the beginning of the cycle, so the first day of bleeding is called "Cycle Day one".
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