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The female organs of reproduction include the ovaries, which produce ova (egg) and progesterone, estrogens and relaxin; the uterine tubes, which transport the ova to the uterus (womb); the vagina; and external organs that constitute the vulva. The mammary glands also are considered part of the female reproductive system.
The ovaries, or female gonads, are paired glands resembling unshelled almonds in size and shape. They are analogous to the male testes. They are positioned in the upper pelvic cavity, one on each side of the uterus. The ovaries are maintained in position by a series of ligaments. The ovary consists of different layers as; Germinal Epithalium, Tunica Albugina and Stroma as well as contain Ovarian Follicles, which are Oocytes (immature ova) and their surrounding tissues in various stages of development (at birth there about 200,000 follicles in each ovary).
Starting with puberty, several follicles respond each month to the rising level of FSH hormone. As the cycle continue and LH hormone is secreted the follicle goes through initial transformation into an egg. At ovulation the transformed follicle enters the uterine tube, where normally fertilization occurs (pregnancy). top
The female body contains two uterine tubes, also called oviducts, which extend laterally from the uterus and transport the ova from the ovaries to the uterus. Measuring about 4 inches long they attach to the superior lateral angle of the uterus. Peristaltic contractions of the tubes help move the ovum down to the uterus. About once a month an immature ovum ruptures from the surface of the ovary, a process called ovulation. The ovum is swept into the tube and moved down along it. If the ovum is fertilized by a sperm cell, it is usually occur at the middle of the tube section called Ampulla. Fertilization may occur at any time up to about 24 hours following ovulation. The fertilized ovum descends into the uterus within 7 days. An unfertilized ovum disintegrates.
The site of menstruation, implantation of a fertilized ovum, development of the fetus during pregnancy, and labor is the uterus. Situated between the urinary bladder and the rectum, the uterus is shaped like an inverted pear. Before the first pregnancy the uterus measures 3 inches long, 2 wide and 1 inch thick. During childbirth, coordinated contractions of the muscles help to expel the fetus from the body of the uterus.
The inner layer of the uterus (stratum functionalis) is shed during menstruation. This causes patches of bleeding in the uterine wall which is the blood seen in menstruation. The functionalis is shed due to a sudden drop in specific hormone levels such as estrogen and progesterone. During menstruation approximately 25 ovarian follicles begin to develop. However by the end of the menstruation only one follicle attains maturity. top
The preovulatory phase, the second phase of the menstrual cycle, is the time between menstruation and ovulation. FSH and LH hormones stimulate the ovarian follicles to produce more estrogens, and this increase in estrogens stimulates the repair of the functionalis (inner wall of the uterus). During the preovulatory phase one of the follicles in the ovary matures into a Graafian Follicle, a follicle ready for ovulation.
Ovulation is the rupture of the Graafian Follicle and release of the immature ovum (egg) into the pelvic cavity. It occurs usually on day 14 in a 28-day cycle. Just prior to ovulation a surge in LH hormone occurs without which ovulation will not happen. An over-the-counter home test that detects the surge in LH hormone surge associated with ovulation is now available. The test predicts ovulation a day in advance.
The postovulatory phase lasts from day 15 to 28 in a 28-day cycle. It represents the time between ovulation and the onset of the next menses. At this phase increased hormonal activity is responsible for preparing the uterus to receive a fertilized ovum. If fertilization does not occur the menses take place as described above. However if fertilization does take place a pregnancy will develop as well as breast development for lactation. top
The advent of menopause is signaled by the climacteric- menstrual cycles become less frequent. The climacteric, which typically begins between ages 40 and 50, results from the failure of the ovaries to respond to the stimulation of hormones. Some women experience hot flashes, copious sweating, headache, hair loss, muscular pains and emotional instability. The cause of menopause is related to a decreasing ability of aging ovaries to respond to FSH and LH hormones. As a result there is a decrease in the production of estrogens by the ovaries. Throughout a woman�s sexual life, some of the primary ovarian follicles grow into mature follicles with each sexual cycle, and eventually most of them degenerate. As the number of primary follicles diminishes, the production of estrogens by the ovary decreases.
The mammary glands are modified sweat glands that lie over the pectoralis major and attached to it by a layer of connective tissue. Internally each mammary gland consists of 15 to 20 compartments separated by adipose tissue. The amount of adipose tissue determines the size of the breasts. However, breast size has nothing to do with the amount of milk produced. At birth, both male and female mammary glands are undeveloped and appear as slight elevation on the chest. With the onset of puberty, the female breasts begin to develop. The changes are correlated to an increased output of estrogens by the ovary. The essential function of the mammary glands is milk secretion and ejection, together called lactation.
Early detection-especially by breast self-examination and mammography- is still the most promising method to increase the survival rate for breast cancer. It is estimated that 95 percent of breast cancer is first detected by women themselves. Each month after the menstrual period the breasts should be thoroughly examined for lumps, puckering of the skin or discharge.