Plant-based antioxidant strategies with potential for preeclampsia prevention: clinical and mechanistic insights.

Preeclampsia is a leading cause of maternal and perinatal morbidity and mortality, driven by oxidative stress, endothelial dysfunction, and systemic inflammation. Current preventive strategies, such as low-dose aspirin, offer modest benefit, highlighting the need for alternative approaches. Medicinal plants with antioxidant and anti-inflammatory properties, long used in maternal health traditions, may provide biological pathways relevant to preeclampsia prevention. This review synthesizes human clinical and mechanistic evidence on four medicinal plants with documented antioxidant activity - Curcuma longa, Moringa oleifera, Orthosiphon aristatus, and Centella asiatica. These botanicals demonstrate potential mechanisms of action including redox modulation, preservation of endothelial function, and suppression of pro-inflammatory pathways, all of which are implicated in preeclampsia pathophysiology. A PRISMA-guided systematic search of PubMed, Scopus, Web of Science, and the Cochrane Library (2000-2025) identified human studies evaluating these plants' effects on oxidative stress and vascular health. Evidence was synthesized narratively due to heterogeneous study designs and outcomes. Most studies were small, often not pregnancy-specific, and used non-standardized botanical formulations. These medicinal plants offer biologically plausible pathways to reduce preeclampsia risk. However, pregnancy-focused randomized trials, dose optimization, pharmacokinetic profiling, and safety evaluations are essential before clinical integration into maternal care.