To investigate the endocrinological relationship between the mother and fetus during pregnancy, endocrinological specificity, particularly the function of the fetal adrenal gland and the placenta, synthesis and metabolism of maternal corticosteroids, we determined maternal serum 11-OHCS in normal and abnormal pregnancy including cases of anencephalus.
The maternal serum 11-OHCS levels in normal pregnancy increased gradually from the 8th week to the terminal stage of pregnancy, were about 2.5 times that of normal nonpregnant women and decreased significantly four weeks after delivery compared with the 10th month of pregnancy.
The diurnal variations in serum 11-OHCS of women in the 10th month of normal pregnancy was almost the same as that of normal nonpregnant women, with high levels observed at 6-10 a.m. and low levels in the afternoon.
The maternal 11-OHCS in abnormal pregnancy showed significantly low levels in abnormal pregnancy with intrauterine fetal death and anencephalus compared with normal pregnant women, and high levels in mild cases and low levels in severe cases were often seen in toxemia pregnancies in the later stage of pregnancy. High levels were also evident in many cases of threatened abortion and premature labor.
The maternal serum 11-OHCS levels of normal pregnancy during labor increased up to the time of delivery and showed a marked decrease thereafter.
Thus, it is assumed that the synthesis of maternal corticosteroids is concerned with function of the fetal adrenal glands and placenta.