placental insufficiency, an abnormal condition of pregnancy, manifested clinically by a decreased rate of fetal and uterine growth. One or more placental abnormalities cause dysfunction of maternal-placental or fetal-placental circulation sufficient to compromise fetal nutrition and oxygenation. Some of the abnormalities that can result in placental insufficiency are abnormal implantation of the placenta, multiple pregnancies, abnormal attachments of the umbilical cord or anomalies of the cord itself, and abnormalities of the placental membranes. Histopathological abnormalities that can cause placental insufficiency include intervillous thrombi, placental infarction, and breaks in the placental membrane that result in fetal bleeding into the maternal circulation. Placental insufficiency also may result from placental senescence in postmaturity; systemic diseases, such as erythroblastosis fetalis and diabetes mellitus; or bacterial, viral, parasitic, or fungal infections. Also called placental dysfunction. See also intrauterine growth retardation, postmature infant.
