The Role of Maternal Vitamin D in the Prevention of Preeclampsia: A Literature Review

Abstract

Preeclampsia remains an important complication of pregnancy and is associated with substantial maternal and perinatal morbidity and mortality. Maternal vitamin D has been proposed to have a preventive role in preeclampsia due to its involvement in placental development, trophoblast invasion, angiogenesis, immune responses, oxidative balance, and vascular regulation. This literature review aimed to evaluate the potential role of maternal vitamin D in preventing preeclampsia by examining the relationship between maternal 25-hydroxyvitamin D [25(OH)D] concentrations and preeclampsia risk, exploring possible underlying mechanisms, and assessing the effects of vitamin D supplementation during pregnancy. A narrative literature review was performed using PubMed, ScienceDirect, and Google Scholar to identify relevant publications from January 2016 through September 2026. Studies involving pregnant women that evaluated maternal vitamin D status or vitamin D supplementation in relation to preeclampsia were considered, including original research, randomized controlled trials, systematic reviews, and meta-analyses. Overall, the reviewed evidence suggests that insufficient maternal 25(OH)D concentrations may be associated with a greater risk of preeclampsia, although the findings vary depending on the timing of vitamin D assessment, criteria used to define vitamin D status, characteristics of the study population, and potential confounding variables. Vitamin D may affect the pathogenesis of preeclampsia by modulating trophoblast invasion, angiogenic processes, antiangiogenic factors, immune regulation, oxidative stress, and vascular function. Evidence from several meta-analyses of randomized controlled trials also indicates that vitamin D supplementation during pregnancy could lower the occurrence of preeclampsia; however, considerable variation among studies remains, and a definitive dose and timing of supplementation have yet to be established. In conclusion, maternal vitamin D appears to have potential as a preventive factor for preeclampsia, although further rigorous research is required to establish the most appropriate supplementation regimen