[C21-steroid profiles in pregnancy associated with intrauterine growth retardation].

To study the steroidal profiles in pregnancy associated with IUGR, maternal serum steroids which included pregnenolone (P5), 16 alpha OH-P5, progesterone (P4) and 16 alpha OH-P4 levels were measured by RIA at 30-41 weeks of gestation and the levels were compared with those obtained from normal pregnancies. Thirty-three pregnancies were diagnosed as IUGR after delivery and 36 pregnancies were used as controls. The levels of P4 and 16 alpha OH-P4 were significantly lower in IUGR pregnancies than those in normal pregnancies, while the levels of P5 and 16 alpha OH-P5 tended to be higher in IUGR than in normal subject. A significant difference was observed between the 16 alpha OH-P4/16 alpha OH-P5 ratio in IUGR and normal pregnancy. When the levels of 16 alpha OH-P5 and 16 alpha OH-P4 were taken into account, 14 of 17 cases of IUGR were discriminated from normal subjects. These results demonstrated for the first time the clinical importance of measuring 16 alpha OH-C21 steroids in case of IUGR. Low delta4/delta5 steroid ratios also indicate that the placental 3 beta HSD activity might be impaired in IUGR pregnancy.