Adjunctive antibiotic treatment in preterm labor and neonatal morbidity: a meta-analysis.
To estimate the effect of prophylactic antibiotics on neonatal mortality and morbidity in patients with preterm labor, based on a meta-analysis of seven published randomized clinical trials. We searched 18 medical data bases, including MEDLINE from 1964 and EMBASE from 1974, to identify all literature included under preterm or premature labor and antibiotics. We scanned all abstracts from the computer printouts, the retrieved full-text reports, the references from each retrieved report, and review articles to determine whether studies met our inclusion criteria. The following criteria were used to select studies for inclusion: article-original published report written in English; study design-randomized controlled trial; population-patients with preterm labor, defined as labor before 37 weeks' gestation; intervention-antibiotic treatment; and one or more of the following outcomes-neonatal mortality, sepsis, pneumonia, respiratory distress syndrome, intraventricular hemorrhage, and necrotizing enterocolitis. We analyzed study patients and methods, and abstracted quantitative outcome data. For each outcome, both odds ratio (OR) and 95% confidence interval (CI) were calculated. Seven trials, published between 1989 and 1995 included a total of 795 patients. Adjunctive antibiotic therapy appeared to reduce the risk of pneumonia (OR 0.45, 95% CI 0.12-1.72) and necrotizing enterocolitis (OR 0.38, 95% CI 0.14-1.08) and to increase the risk of neonatal mortality (OR 3.25, 95% CI 0.93-11.38), but it had no effect on neonatal sepsis (OR 0.98, 95% CI 0.34-2.83), respiratory distress syndrome (OR 0.93, 95% CI 0.54-1.87), and intraventricular hemorrhage (OR 1.01, 95% CI 0.20-5.10). None of the effects observed reached a significance level of P < .05. The results of this meta-analysis do not support the routine use of adjunctive antibiotic treatment in patients with preterm labor diagnosed on the basis of subjective uterine contractions and the resulting cervical changes.