Background: The fetal membranes are the thin tissue that surround the fetus during gestation, and critical for maintaining a pregnancy to delivery. Objective: To evaluate the values of platelet count and mean platelet volume (MPV) obtained from maternal serum during pregnancy to predict subsequent preterm premature rupture of membranes (PPROM). Patients and Methods: This study was a prospective Cohort study that was conducted on 300 cases of pregnant women at Obstetric and gynecological department at El-Hussein University Hospital. All patients met the inclusion criteria and were divided into two groups, Group I (PPROM group) that included 22 pregnant women with history of vaginal fluid leakage and diagnosed as PPROM and Group II (Control group) which included 278 pregnant women with gestational age between 37 - 41 weeks and without any history of complications throughout the pregnancy as a control group. Results: As regard the area under curve, cutoff and validity of PLT regard detection of PPROM, Significant AUC with cutoff >258 with sensitivity 83.3% and specificity 75.0%. The overall accuracy of MPV for detecting PPROM was found to be superior to platelet count. Conclusion: MPV is a cheap, rapid and easily applicable test for determining the patients at risk for PPROM. Due to multifactorial origin of PPROM, early detection of all patients with a single test is rather difficult. In order to develop an accurate and efficient method in the estimation of the risk of PPROM, screening strategies combining MPV with other biological markers should be considered.