EP17.65: Evaluating first trimester PAPP‐A and free b‐HCG as risk factors for preterm membrane rupture

The study aimed to compare the concentrations of PAPP-A protein and bHCG in absolute and normalised (multiple of medians - MoM) forms between 11 and 13+6 weeks of gestation in pregnant women who experienced preterm prelabour rupture of membranes (pPROM) compared to those without this complication. This research seeks to illuminate potential early biomarkers for pPROM risk. We included 664 patients with complete follow-up until delivery. The incidence of pPROM in the cohort was carefully documented (regardless of whether it led to preterm birth). We compared the median concentrations of free bHCG and PAPP-A in the first trimester in both groups, in raw and normalised forms, using the robust Kruskal-Wallis U test to calculate the significance of differences, with a p-value <0.05 considered statistically significant. The cohort's incidence of pPROM was 4.2%. Significant differences were observed between the groups in all studied parameters (see table 1). Notably, in the group with pPROM, we observed lower concentrations of fb-HCG in both absolute values and normalised form, along with reduced PAPP-A levels. Women experiencing pPROM during pregnancy have lower first trimester concentrations of fb-HCG and PAPP-A, indicating these markers may serve as early predictors for pPROM. Further research is needed to confirm the clinical significance and predictive value of these findings.