The value of qualitative detection of human chorionic gonadotropin in vaginal washing fluid for diagnosis of preterm premature rupture of membranes

Objective: This study was performed to determine the sensitivity and specificity of qualitative hCG testing of vaginal washings for diagnosis of preterm premature rupture of membranes (PPROM). Methodology: A total of 92 singleton pregnant women at 20 – 37 weeks of gestation were placed in two equal groups of documented rupture of membranes and intact membranes as control. Confirmatory tests included pooling of amniotic fluid in the vaginal vault with positive ferning test. Patients with vaginal bleeding and obvious fetal anomaly were excluded. After cleaning the vagina with a sterile tampon and irrigation with 5 ml sterile saline, fluids were collected from the posterior vaginal fornix. Samples were tested by a pregnancy test strip with sensitivity of 25 mIU/ml. Data were collected and analyzed using t-test, Mann-Whitney, Chi- squared, Fisher’s exact tests. Results: The groups had similar demographic characteristics. The hCG test was positive in 38 (83%) of the ruptured membranes group and in 4 (8%) of the control group. Sensitivity, specificity, positive predictive value, and negative predictive value were shown to be 83%, 91%, 90%, and 84%, respectively. Conclusions: The qualitative determination of hCG in vaginal washings proved a simple, rapid, noninvasive, and reliable test in the diagnosis of PPROM.