- The uterus (womb) is a hollow, pear-shaped organ located in a woman's lower abdomen between the bladder and the rectum. The narrow, lower portion of the uterus is the cervix; the broader, upper part is the corpus. The corpus is made up of two layers of tissue. In women of childbearing age, the inner layer of the uterus (endometrium) goes through a series of monthly changes known as the menstrual cycle. Each month, endometrial tissue grows and thickens in preparation to receive a fertilized egg. Menstruation occurs when this tissue is not used, disintegrates, and passes out through the vagina. The outer layer of the corpus (myometrium) is muscular tissue that expands during pregnancy to hold the growing fetus and contracts during labor to deliver the child.
* * *The hollow muscular organ in which the impregnated ovum is developed into the child; it is about 7.5 cm in length in the nonpregnant woman, and consists of a main portion (body) with an elongated lower part (cervix), at the extremity of which is the opening (external os). The upper rounded portion of the u., opposite the os, is the fundus, at each extremity of which is the horn marking the part where the uterine tube joins the u. and through which the ovum reaches the uterine cavity after leaving the ovary. The organ is passively supported in the pelvic cavity by the cardinal ligaments and by the anteflexion and anteversion of the normal u., which places its mass superior to the bladder; it is actively supported by the tonic and phasic contraction of the muscles of the pelvic floor. SYN: metra, womb. [L.]- anomalous u. a malformed u. caused by abnormal development or fusion of the paramesonephric ducts.- u. arcuatus SYN: arcuate u..- bicornate u. a u. that is more or less completely divided into two lateral horns as a result of imperfect union of the paramesonephric ducts; it differs from septate u., in which there is no external mark of separation; in bicornate u., the cervix may be single (u. bicornis unicollis) or double (u. bicornis bicollis). SYN: bifid u., u. bicornis, u. bifidus.- u. bicornis SYN: bicornate u..- u. bicornis bicollis bicornate u..- u. bicornis unicollis bicornate u..- bifid u. SYN: bicornate u..- u. bifidus SYN: bicornate u..- biforate u. septate u. in which the cervix is divided into two by a septum. SYN: double-mouthed u., u. biforis.- u. biforis SYN: biforate u..- u. bilocularis SYN: septate u..- u. bipartitus SYN: septate u..- cordiform u. an incomplete u. bicornis with a wedge-shaped depression at the fundus. SYN: heart-shaped u., u. cordiformis.- u. cordiformis SYN: cordiform u..- Couvelaire u. extravasation of blood into the uterine musculature and beneath the uterine peritoneum in association with severe forms of abruptio placentae. SYN: uteroplacental apoplexy.- u. didelphys double u. with double cervix and double vagina; due to failure of the paramesonephric ducts to unite. [G. di-, two, + delphys, womb]- double-mouthed u. SYN: biforate u..- duplex u. any u. with double lumen (u. didelphys, u. bicornis bicollis, or septate u.). SYN: u. duplex.- heart-shaped u. SYN: cordiform u..- incudiform u. u. bicornis in which the fundus between the two cornua is broad and flat. SYN: triangular u., u. incudiformis, u. triangularis.- u. incudiformis SYN: incudiform u..- septate u. a u. divided into two cavities by an anteroposterior septum. SYN: bipartite u., u. bilocularis, u. bipartitus, u. septus.- u. septus SYN: septate u..- subseptate u. an incomplete u. septus. SYN: u. subseptus.- u. subseptus SYN: subseptate u..- triangular u. SYN: incudiform u..- unicorn u. a u. in which only one lateral half exists, the other half being undeveloped or absent. SYN: u. unicornis.- u. unicornis SYN: unicorn u..
* * *uter·us 'yüt-ə-rəs n, pl uteri -.rī also uter·us·es an organ in female mammals for containing and usu. for nourishing the young during development prior to birth that consists of a greatly modified and enlarged section of an oviduct (as in rodents and marsupials) or of the two oviducts united (as in the higher primates including humans), that has thick walls consisting of an outer serous layer, a very thick middle layer of smooth muscle, and an inner mucous layer containing numerous glands, and that during pregnancy undergoes great increase in size and change in the condition of its walls called also womb see CERVIX (2a), CORPUS UTERI, endometrium, fundus (c), myometrium, perimetrium
* * *n.the part of the female reproductive tract that is specialized to allow the embryo to become implanted in its inner wall and to nourish the growing fetus from the maternal blood. The nonpregnant uterus is a pear-shaped organ, about 7.5 cm long. It is suspended in the pelvic cavity by means of peritoneal folds (ligaments) and fibrous bands. The upper part is connected to the two Fallopian tube and the lower part joins the vagina at the cervix. The uterus has an inner mucous lining (endometrium) and a thick wall of smooth muscle (myometrium). During childbirth the myometrium undergoes strong contractions to expel the fetus through the cervix and vagina. In the absence of pregnancy the endometrium undergoes periodic development and degeneration (see menstrual cycle).• uterine adj.
* * *uter·us (uґtər-əs) pl. uґteri [L., from Gr. hystera] [TA] the hollow muscular organ in female mammals in which the blastocyst normally becomes embedded and in which the developing embryo and fetus is nourished. In the nongravid human, it is a pear-shaped structure, about 8 cm in length, consisting of a fundus, body, isthmus, and cervix. Its cavity opens into the vagina below, and into the uterine tube on either side at the cornu. It is supported by direct attachment to the vagina and by indirect attachment to various other nearby pelvic structures. Called also metra. uterine adj
Medical dictionary. 2011.