Introduction: Chorioamnionitis is one of the most important maternal complications in the expectant management of patients with preterm premature rupture of membranes (PPROM). Procalcitonin (proCT), the precursor of the hormone calcitonin, is used to differentiate bacterial infections from non-bacterial ones. The objective of the study was to determine the efficacy of maternal serum procalcitonin levels in the early prediction of chorioamnionitis in women with PPROM.