Failure of 17-hydroxyprogesterone to reduce neonatal morbidity or prolong triplet pregnancy: a double-blind, randomized clinical trial

To test whether 17 alpha-hydroxyprogesterone caproate (17P) will reduce neonatal morbidity by increasing gestational age at delivery in triplet pregnancies.

Double-blind, randomized clinical trial. Mothers carrying trichorionic-triamniotic triplets were randomly assigned (in a 2:1 ratio) to weekly injections of 250 mg of 17P or placebo, starting at 16-22 weeks and continued until 34 weeks. Primary outcome was composite neonatal morbidity.

Fifty-six women were randomized to 17P and 25 to placebo. Composite neonatal morbidity occurred with similar frequency in the 17P and placebo groups (38% vs 41%, respectively; P = .71). Mean gestational age at delivery was not affected by 17P (31.9 vs 31.8 weeks; P = .36). There were 13 midtrimester fetal losses with 17P vs none with placebo (P < .02).

In triplet pregnancy, prophylactic treatment with 17P did not reduce neonatal morbidity or prolong gestation but was associated with increased midtrimester fetal loss.