INHIBITION OF PROSTAGLANDIN-INDUCED UTERINE ACTIVITY BY NIFEDIPINE

The effects of the calcium antagonist, nifedipine, on uterine activity induced by prostaglandins F2α (PGFZ2α) and E2 (PGE2) were studied in women undergoingtherapeutic midtrimester abortion, and in patients with a missed abortion in the 16th to 27th week of pregnancy. In the five subjects receiving intra‐amniotic PGF2α (25 to 40 mg) for midtrimester abortion, nifedipine (30 mg orally) decreased uterine activity from a mean of 372 to 203 Montevideo Units. The effect on the intensity of the contractions was pronounced; frequency and basal tone were little affected. In patients with missed abortion, uterine contractions were induced by extra‐amniotic application of PGE2 (0.5 to 1.5 mg) in a viscous gel. The activity was often more irregular than that in the women receiving intra‐amniotic PGF2α. However, nifedipine (30 mg orally) had a marked inhibitory effect on the uterine contractions. It is concluded that nifedipine can be used for treatment of uterine hyperactivity induced by prostaglandins. Combined treatment with β2‐adrenoceptor stimulants might be considered. Copyright © 1979, Wiley Blackwell. All rights reserved