Premature rupture of membranes and spontaneous preterm labor: maternal endometritis risks.

Preterm and term deliveries were analyzed at The Johns Hopkins Hospital from January 1, 1976, through December 31, 1977, to determine maternal infection risks associated with premature rupture of the membranes (PROM). Gravidas who delivered preterm infants demonstrated an increased incidence of endometritis with or without PROM. The risk of endometritis attributable solely to PROM was insignificant compared with the risk attributable to preterm delivery. These findings implicate infection in the mechanism of preterm labor, with or without PROM.