- - d. basalis the area of endometrium between the implanted chorionic vesicle and the myometrium, which develops into the maternal part of the placenta. SYN: d. serotina.- d. capsularis the layer of endometrium overlying the implanted chorionic vesicle; it becomes progressively attenuated as the chorionic vesicle enlarges and, by the fourth month, is squeezed against the d. parietalis and thereafter undergoes rapid regression. SYN: d. reflexa, membrana adventitia (2).- ectopic d. decidual cells which may be found in the cervix, appendix, or areas other than the endometrium.- d. parietalis the altered mucous membrane lining the main cavity of the pregnant uterus other than at the site of attachment of the chorionic vesicle. SYN: d. vera.- d. reflexa SYN: d. capsularis.- d. vera SYN: d. parietalis.
* * *1) the part of the mucous membrane lining the uterus that in higher placental mammals undergoes special modifications in preparation for and during pregnancy and is cast off at parturition, being made up in the human of a part lining the uterus, a part enveloping the embryo, and a part participating with the chorion in the formation of the placenta see DECIDUA BASALIS, DECIDUA CAPSULARIS, DECIDUA PARIETALIS2) the mucous membrane of the uterus cast off in the ordinary process of menstruationde·cid·u·al -ə-wəl adj
* * *n.the modified mucous membrane that lines the wall of the uterus during pregnancy and is shed with the afterbirth at parturition (see endometrium). There are three regions: the decidua capsularis, a thin layer that covers the embryo; the decidua basalis, where the embryo is attached; and the <
, which is not in contact with the embryo.• decidual adj.
* * *de·cid·ua (də-sidґu-ə) [L., from deciduus, from decidere to fall off] the endometrium of the pregnant uterus, all of which, except the deepest layer, is shed at parturition. Called also decidual or deciduous membrane. decidual adj
Medical dictionary. 2011.