Premature rupture of membranes: the role of C-reactive protein in the prediction of chorioamnionitis.

A group of 52 patients with premature rupture of the membranes (PROM) before 34 weeks' gestation were evaluated prospectively and managed expectantly. Of 42 patients who were delivered of their infants, 26 (61.9%) had significant chorioamnionitis on histopathology, and 18 had positive microbial cultures at delivery. However, only seven patients (16.7%) developed clinical signs of chorioamnionitis. There were no maternal deaths or perinatal deaths attributable to sepsis. Only two infants (less than 5%) had positive blood cultures. All patients were assessed daily for the development of chorioamnionitis. Amniocenteses were not routinely performed. White blood cell counts, band neutrophil counts, and erythrocyte sedimentation rate determinations were found to be unreliable. C-reactive protein determinations were found most reliable with a high sensitivity and specificity. Elevated C-reactive protein levels correlated better with pathologic confirmation of chorioamnionitis than with the clinical febrile morbidity. Clinical implications for the management of PROM are discussed.