..... Click the link for more information. . The human uterus is pear-shaped and about 3 in. (7.6 cm) long (it expands greatly during pregnancy); it normally lies in the pelvis, where it is supported by a ligament on either side extending to the pelvic wall. The body of the uterus tapers down to a necklike structure (cervix) that leads into the vagina. On either side of the uterus is an oviduct (called fallopian tube, or uterine tube, in humans) from 3 to 5 in. (7.6–12.7 cm) long, one end opening into the uterus and the other, wide-mouthed, ends in close proximity to an ovary ovary, ductless gland of the female in which the ova (female reproductive cells) are produced. In vertebrate animals the ovary also secretes the sex hormones estrogen and progesterone , which control the development of the sexual organs and the secondary sexual
..... Click the link for more information. . These oviducts serve as passageways for the ova to reach the uterus. Fertilization occurs in the oviduct; the fertilized ovum then continues into the uterus, where it becomes implanted in the lining of that organ, also known as the endometrium. If fertilization does not occur, the ovum and the lining of the uterine wall pass out of the body through the vagina (see menstruation menstruation, periodic flow of blood and cells from the lining of the uterus in humans and most other primates, occurring about every 28 days in women. Menstruation commences at puberty (usually between age 10 and 17).
..... Click the link for more information. ). Endometrial tissues then build up again in the uterus in anticipation of the next release of an ovum.
Diseases that can affect the uterus include various sexually transmitted diseases sexually transmitted disease (STD) or venereal disease, term for infections acquired mainly through sexual contact. Five diseases were traditionally known as venereal diseases: gonorrhea , syphilis , and the less common granuloma inguinale,
..... Click the link for more information. , pelvic inflammatory disease pelvic inflammatory disease (PID), infection of the female reproductive organs, usually resulting from infection with the bacteria that cause chlamydia or gonorrhea .
..... Click the link for more information. , and endometriosis endometriosis (ĕn'dəmē'trē-ō`sĭs)
..... Click the link for more information. , as well as benign or malignant tumors. Benign tumors may be removed without damage to the uterus, although in cases where the tissue is found to be cancerous, the entire uterus and cervix may have to be removed in a procedure known as hysterectomy hysterectomy (hĭstərĕk`təmē), surgical removal of the uterus .
..... Click the link for more information. . Prolapse of the uterus occurs when weakened supporting structures allow the uterus to tilt and slip downward into the vagina. See also reproductive system reproductive system, in animals, the anatomical organs concerned with production of offspring. In humans and other mammals the female reproductive system produces the female reproductive cells (the eggs, or ova) and contains an organ in which development of the fetus
..... Click the link for more information. .
uterus
or wombInverted-pear-shaped organ of the female reproductive system, in which the embryo and fetus develop during pregnancy. Lying over and behind the bladder, it is 2.5–3 in. (6–8 cm) long and about 2.5 in. (6 cm) across at the top, where the fallopian tubes enter it; at the other end, the cervix extends down into the vagina. The uterine lining (endometrium), a moist mucous membrane, changes in thickness during the menstrual cycle (see menstruation), being thickest at ovulation in readiness for a fertilized egg. The uterine wall, about 1 in. (2.5 cm) thick, expands and becomes thinner as a fetus develops inside. The cervix expands to about 4 in. (10 cm) for delivery. Disorders of the uterus include infections, benign and malignant tumours, prolapse, endometriosis, and fibroids (leiomyomas; see muscle tumour).
uterus
Uterus
The hollow, muscular womb, being an enlarged portion of the oviduct in the adult female. An adult human uterus, before pregnancy, measures 3 × 2 × 1 in. (7.5 × 5 × 2.5 cm) in size and has the shape of an inverted, flattened pear. The paired Fallopian tubes enter the uterus at its upper corners; the lower, narrowed portion, the cervix, projects into the vagina (see illustration). Normally the uterus is tilted slightly forward and lies behind the urinary bladder.
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The lining, or mucosa, responds to hormonal stimulation, growing in thickness with a tremendous increase in blood vessels during the first part of the menstrual cycle. If fertilization does not occur, the thickened vascular lining is sloughed off, producing the menstrual flow at the end of the cycle, and a new menstrual cycle begins with growth of the mucosa. When pregnancy occurs, the mucosa continues to thicken and forms an intimate connection with the implanted and enlarging placenta. See Menstruation, Reproductive system
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