Changes in the concentration of cortisol in amniotic fluid after intra-amniotic prostaglandin for midtrimester abortion.

The effects of intra-amniotic prostaglandin E2 (PGE2) and PGF2alpha on the concentration of cortisol in amniotic fluid and in maternal peripheral plasma of patients undergoing abortion between 16 and 23 weeks gestation have been examined. There was a significant (P less than 0-01) increase in the concentration of cortisol in amniotic fluid for hours after PGE2, but not after PGF2alpha. The concentration of cortisol in the maternal peripheral plasma increased in both groups with the progression of abortion, but the levels were not significantly correlated with those in amniotic fluid. These results suggest that by mid-pregnancy fetal cortisol production can be stimulated by PGE2 but the mechanism of this action remains to be elucidated.