Introduction Preeclampsia (PE) remains a significant cause of maternal and neonatal morbidity and mortality worldwide, necessitating effective prevention strategies. Low-dose aspirin has been proposed as a preventive measure for women at high risk of developing PE, given its role in modulating platelet aggregation and improving placental perfusion. However, questions regarding optimal dosage, timing, and effectiveness across diverse populations persist. This systematic review and meta-analysis aimed to synthesize evidence from randomized controlled trials (RCTs) to evaluate the efficacy of low-dose aspirin in reducing the incidence of PE.

Methods A comprehensive search was conducted across databases and registers, identifying 850 records. After removing duplicates and excluding studies based on eligibility criteria, 33 RCTs were included. Data were extracted on aspirin dosage, timing of initiation, continuation duration, and PE outcomes. Meta-analysis was performed to evaluate the protective effect of aspirin, and study quality was assessed using bias scoring.

Results Low-dose aspirin (75–150 mg) significantly reduced PE incidence in high-risk women. Early initiation, particularly between 12–16 weeks, demonstrated enhanced efficacy. Higher doses, such as 150 mg, were associated with better outcomes compared to lower doses. Variability among studies was noted due to differences in populations, aspirin protocols, and methodological quality. Bias assessments indicated moderate quality across most studies.

Conclusion Low-dose aspirin, initiated early in pregnancy, effectively reduces PE risk in high-risk women. Findings support integrating aspirin therapy into prenatal care guidelines, with tailored dosing based on patient risk profiles. Future research should refine protocols and explore long-term maternal and neonatal outcomes.

The authors have declared no competing interest.

CTRI/2023/12/060983 [Registered on: 29/12/2023] Trial Registered Prospectively. Acknowledgement Number REF/2023/12/076358

This research received funding from Indian Council of Medical Research (ICMR). File no EM/Dev/SG/196/1111/2023 E-office-171811 Contact no +91-11-26588895

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