Ultrasonographic assessment of fetal adrenal gland and placenta: correlation with estrogen in maternal urine.

Forty-eight ultrasonographic examinations done to assess growth of the fetal adrenal gland and placental aging were performed on 17 normal fetuses and 7 fetuses with intrauterine growth retardation (IUGR). Gestational age ranged from 30 to 40 weeks. High correlations of the area of fetal adrenal gland (FAGA) with gestational age were noted in the normal fetuses (r = 0.96, p less than 0.001) and IUGR (r = 0.93, p less than 0.001), respectively. FAGA correlated well with the level of estrogens in the maternal urine (r = 0.65, p less than 0.001). When the value of FAGA was 300 mm2 and over, the level of estrogens in the maternal urine was 20 mg/day and over, and all were normal fetuses. In cases of grade I and II placentas, the mean values of FAGA in normal fetuses were larger than those in IUGR, respectively (p less than 0.001). In the case of IUGR with placental infarction and hematoma associated with severe toxemia of pregnancy, the FAGA was significantly small.