Meta-analysis of efficacy and pregnancy outcomes of low molecular weight heparin combined with magnesium sulfate in the treatment of preeclampsia

Objective To evaluate the efficacy of low molecular weight heparin (LMWH) combined with magnesium sulfate in preeclampsia and its effect on pregnancy outcomes through a meta-analysis. Methods Randomized controlled trials (RCTs) comparing LMWH plus magnesium sulfate versus magnesium sulfate alone in preeclampsia were searched in PubMed, Embase, Cochrane Library, and CNKI until May 2025. Study selection, data extraction, and quality assessment were performed independently. Meta-analysis and sensitivity analyses were conducted using RevMan 5.4.1 and Stata 18. Results Twenty-three RCTs involving 2085 preeclampsia patients were included. Compared to magnesium sulfate alone, combination therapy significantly reduced systolic/diastolic/mean arterial pressure, D -dimer, 24-hour urinary protein, serum creatinine, endothelin-1, hs-CRP, sFlt-1, and VCAM-1, while prolonging prothrombin and activated partial thromboplastin times (all P < 0.01). The combined treatment improved overall efficacy (OR=10.38, 95% CI: 4.61–23.38) and neonatal 1-minute Apgar scores, while lowering risks of adverse pregnancy outcomes (OR=0.30, 95% CI: 0.22–0.41) and adverse neonatal outcomes (OR=0.32, 95% CI: 0.23–0.45). Subgroup analysis showed reduced rates of HELLP syndrome, placental abruption, postpartum hemorrhage, fetal asphyxia, and neonatal asphyxia (all P < 0.05). No significant publication bias was detected (Egger’s test P = 0.143). Conclusion LMWH combined with magnesium sulfate improves treatment efficacy, hemodynamic and coagulation parameters, renal function, and inflammatory markers in preeclampsia, while reducing adverse pregnancy and neonatal outcomes, supporting its clinical application.