A study published in the International Journal of Gynecology and Obstetrics aimed that determining the diagnostic value of vaginal discharge concentrations of beta human chorionic gonadotropin (β-hCG), creatinine, and urea to identify premature rupture of membranes (PROM). The results showed that although the vaginal discharge concentrations of all 3 markers exhibited favorable predictive value for the diagnosis of PROM, beta-hCG displayed greater diagnostic accuracy than either urea or creatinine.

In this observational cross-sectional study, 120 women who were admitted to a hospital at 28-41 weeks of pregnancy were included. Women with positive pooling and nitrazine test results were allocated to the PROM group (n=60) while those with negative results were assigned to the control group (n=60). Mean concentrations of beta-hCG, urea, and creatinine were higher in the PROM group in contrast to the control group. The diagnostic accuracies as defined by area under the curve for creatinine, urea, and beta-hCG were 0.891, 0.895, and 0.908, respectively. The corresponding optimal cut-off figures were 20.33 μmol/L, 0.94 mmol/L, and 39.5 IU/L, respectively.