R. Romero et al., ANTIBIOTIC-TREATMENT OF PRETERM LABOR WITH INTACT MEMBRANES - A MULTICENTER, RANDOMIZED, DOUBLE-BLINDED, PLACEBO-CONTROLLED TRIAL, American journal of obstetrics and gynecology, 169(4), 1993, pp. 764-774
OBJECTIVE: Although an association between subclinical intrauterine in
fection and preterm birth is well established, there is conflicting ev
idence regarding the benefits of antibiotic administration to women in
preterm labor with intact membranes. We attempted to determine the ef
fect of ampicillin-amoxicillin and erythromycin treatment on prolongat
ion of pregnancy, the rate of preterm birth, and neonatal morbidity in
patients with preterm labor and intact membranes. STUDY DESIGN: A mul
ticenter, randomized, double-blinded, placebo-controlled trial was des
igned and implemented by the Maternal-Fetal Medicine Units Network of
the National Institute of Child Health and Human Development. Two hund
red seventy-seven women with singleton pregnancies and preterm labor w
ith intact membranes (24 to 34 weeks) were randomly allocated to recei
ve either antibiotics or placebos. RESULTS: Of the 2373 patients scree
ned for participation in this study in six medical centers, 277 women
were enrolled (n = 133 for antibiotics group vs n = 144 for placebo gr
oup). In each study group, 60% of patients completed all the study med
ications. The overall prevalence of microbial invasion of the amniotic
cavity was 5.8% (14/239). No significant difference between the antib
iotic group and the placebo group was found in maternal outcomes, incl
uding duration of randomization-to-delivery interval, frequency of pre
term delivery (<37 weeks), frequency of preterm premature rupture of m
embranes, clinical chorioamnionitis, endometritis, and number of subse
quent admissions for preterm labor. Similarly, no significant differen
ce in neonatal outcomes could be detected between the two groups inclu
ding respiratory distress syndrome, bronchopulmonary dysplasia, intrav
entricular hemorrhage, sepsis, and admission and duration of newborn i
ntensive special care unit hospitalization. CONCLUSION: The results of
this study do not support the routine use of antibiotic administratio
n to women in preterm labor with intact membranes.