Uteroplacental blood flow measurement using radioisotopes in small placentas.

In 25 pregnant females with a placental weight below the 20th percentile uteroplacental blood flow measurements using 113mIn-transferrin were performed in the 3rd trimester of pregnancy. Twelve patients with pregnancy-induced hypertension (PIH) were compared to 13 females with normal blood pressures. The results of uteroplacental blood flow measurements showed normal flow patterns in only 6 of the 25 subjects and were significantly worse in the group with PIH. Babies of patients with PIH had a mean birth weight of 1,100 g at a mean gestational age of 34.2 weeks versus 1,752 g and 37.4 weeks for newborns without PIH. Perinatal mortality was significantly higher in the PIH group. In combination with a small placenta PIH compounds the fetal risk.