Maternal serum syndecan-1 levels in preterm prelabor rupture of membranes and potential predictor of adverse perinatal outcomes: A case-control study.

Objective: This study's primary objective was to compare the levels of maternal serum syndecan-1 (SYD-1) in pregnant women with preterm prelabor rupture of membranes (PPROM) and healthy controls. The secondary objectives involved measuring the predictive capacity of SYD-1 for composite adverse perinatal outcomes (CAPO) and examining the association between SYD-1 levels and CAPO within the PPROM cohort.

Methods: This prospective observational study was conducted at the Perinatology Department of Ankara Etlik City Hospital between November 2024 and April 2025. The study comprised 64 patients diagnosed with PPROM at 24-34 weeks of gestation and 64 healthy pregnant women matched for gestational age (GA) at sampling, as well as for maternal age, gravidity, and parity. Maternal serum samples were collected, and SYD-1 levels were measured using ELISA. Clinical, laboratory, and neonatal data were compared between groups. In the PPROM group, predictors of CAPO were analyzed using univariable and multivariable logistic regression.

Results: Maternal SYD-1 levels were significantly higher in the PPROM group (19.29 ± 3.13 ng/mL) compared to the control group (14.67 ± 3.67 ng/mL) (mean difference: 4.62 ng/mL, 95% confidence interval [CI]: 3.43-5.81, P < 0.001). Among PPROM patients who developed CAPO, SYD-1 levels were also significantly elevated (20.04 ± 2.78 ng/mL vs. 16.86 ± 3.06; mean difference: 3.18 ng/mL, 95% CI: 1.50-4.86, P < 0.001). ROC analysis demonstrated good predictive performance in predicting CAPO (AUC = 0.785). Multivariable logistic regression analysis suggested that SYD-1 was associated with CAPO after adjusting for GA at the time of PPROM, latency period, maternal inflammatory markers, and GA at delivery (adjusted odds ratio: 1.71, 95% confidence interval: 1.15-2.54, P = 0.008).

Conclusion: Maternal serum SYD-1 levels are significantly higher in PPROM patients compared to controls and might be associated with the development of CAPO. However, the cross-sectional nature of SYD-1 measurement and the multifactorial etiology of CAPO necessitate cautious interpretation. Prospective studies with serial measurements and larger cohorts are needed to confirm these preliminary findings and to better define their clinical significance.