• Complement;
  • prematurely ruptured membranes

ABSTRACT: Physiologic changes occurring during the latent period of prematurely ruptured membranes (PRM) are poorly understood. Indicators predicting maternal and neonatal infectious morbidity do not correlate well with clinical outcomes. A previous report suggested that in vivo complement consumption occurred in response to the event of membrane rupture. In this prospective study, complement activity was measured serially throughout the latent period in cases of preterm PRM. In addition to total hemolytic complement activity (CH50), C3-proactivator (C3PA), a primary component of the alternate complement pathway, was measured in maternal and cord sera. As with CH50, cord serum C3PA levels are significantly less than those in matched maternal samples. Neither maternal nor cord serum complement activity correlated with either the duration of the latent period or maternal-neonatal infection.