Initial experience using Sivelestat to manage preterm labor with a bulging fetal membrane in pregnant women.

Intrauterine infection and inflammation are recognized as major contributors to the onset of preterm labor. We describe two cases of severe preterm labor with bulging membrane that were treated by intravenous injection of Sivelestat, a neutrophil elastase inhibitor. Ritodrine hydrochloride and magnesium sulfate were intravenously administered for tocolysis, and ampicillin was provided as an antibiotic. Urinary trypsin inhibitor (UTI) was administered transvaginally. Sivelestat was infused intravenously at 4.8 mg kg(-1) day(-1) through the maternal vein. No side effects were observed. Levels of interleukin (IL)-6 and IL-8 in amniotic fluid decreased, and gestations were prolonged without complications for >1 week. Two healthy infants were delivered. Our experience suggests that multidrug therapy with Sivelestat offers a new therapeutic strategy for preterm labor, but further investigations of the indications, administration period and dosage are required.