Diagnostic Value of Prolactin and B-Hcg Levels of Vaginal Fluid in Diagnosis of Premature Rupture of Membranes

Introduction: The aim of this study was diagnosis of premature rupture of membranes in suspected patients by measurement of prolactin and B-hCG levels in vaginal washing in order to reduce perinatal mortality and morbidity. Methods: The study included 211 pregnant women who were referred to the emergency of Imam Hossein hospital at 28-38 weeks of pregnancy for leakage or prenatal care from April, 2007 to April, 2008. The expulsion of fluid from the cervix was evaluated and fern and nitrazin tests were done. B-hCG and prolactin levels of vaginal washing fluid were measured. The presence of 2 of 3 parameters of fern test, nitrazin and cervical fluid was defined as absolutely premature rupture of membranes. Mann-Withney U-test was used for analysis. The Roc curve was calculated. Results: There were 132 patients in PROM group and79 patient in the control group. The average age in the PROM and control groups was 26.9‌±6.08 and 26.2±4.84 years, respectively(P=0.074). Both groups were matched for parity and gravidity. Prolactin levels in PROM group were 2930±3737mIU/l versus 23.18±120mIU/l in the control group (P=0.000). B-hCG was 439.78±1867mIU/l in PROM and 17.72±30mIU/l in control group (p=0.000). Sensitivity and specificity of prolactin according to cut-off of 16.0 mIU/l was 79.41% and 96%, respectively. Sensitivity and specificity for B-hCG with cut-off point of 12.5 was 69.85% and 69.33%, respectively. Conclusion: The measurement of prolactin and B-hCG levels in patients with suspected premature rupture of membranes can help in decision-making and treatment.