A randomized, prospective study of adjunctive Ampicillin in preterm labor

Abstract

Acute amniotic fluid infection has emerged as a possible cause of many heretofore unexplained preterm births. Our purpose was to determine the effect of ampicillin in the prolongation of pregnancies receiving tocolysis for preterm labor. A blinded, placebo-controlled, randomized trial was conducted to study ampicillin in women hospitalized for preterm labor between 24 and 37 weeks' gestation. A total of 60 patients with intact membranes and without chorioamnionitis who were receiving magnesium sulfate were screened. Thirty women with preterm labor received ampicillin, and 30 received placebos. The primary end point was prolongation of gestation. There was no difference in age of delivery (37.6±9.7 days vs 36.08±3.9 days, P=0.085) and no difference in retardation of delivery (4.7±3.1 vs 4.1±2.1, P=0.39). The mean degree of preterm delivery were 0.62±1.93 and 1.8±3.3 weeks in ampicillin and placebo groups, respectively (not significant, P>0.1). Conclusions: Ampicillin had no effect on interval to delivery or duration of pregnancy in women treated for preterm labor. So rotine clinical use of ampicillin during tocolysis should not be recommended