Administration of steroids after 34 weeks of gestation enhances fetal lung maturity profiles

To estimate the effect of antenatal glucocorticoid administration on fetal lung maturity in pregnancies with known fetal lung immaturity between the 34th and 37th weeks of gestation.

Pregnancies between 34(0/7) and 36(6/7) weeks undergoing amniocentesis to determine fetal lung maturity were targeted. Women with negative results (TDx-FLM-II <45 mg/g) were randomly assigned to intramuscular glucocorticoid injection or no treatment. A repeat TDx-FLM-II test was obtained 1 week after enrollment.

Thirty-two women who met inclusion criteria were randomly assigned. Seven women delivered within a week of testing for fetal lung maturity, and were excluded from the analysis. Ten received glucocorticoid and 15 did not. Women assigned to glucocorticoids had a mean increase TDx-FLM-II in 1 week of 28.37 mg/g. Women assigned to no-treatment had an increase of 9.76 mg/g (P < .002).

A single course of intramuscular glucocorticoids after 34 weeks in pregnancies with documented fetal lung immaturity significantly increases TDx- FLM-II.