Beyond deficiency prevention: meteorological determinants and nonlinear associations of maternal vitamins D, A, and E with perinatal outcomes in 10,824 Chinese pregnancies.

Objective: To examine meteorological factors associated with maternal vitamins D, A, and E and their associations with delivery and neonatal outcomes in central China. Methods: In this retrospective cross-sectional analysis of 10,824 third-trimester women who delivered at 37 weeks or later in Wuhan (2020-2023), serum vitamin levels were measured by high-performance liquid chromatography. Daily temperature, humidity, precipitation, and wind speed were matched to individual blood collection dates. Multivariable logistic regression and restricted cubic spline models were used to evaluate associations with fetal distress, meconium-stained amniotic fluid, premature rupture of membranes (PROM), low birth weight, and macrosomia. Results: Vitamin D deficiency (30.2%), vitamin A deficiency (5.5%), and vitamin E excess (41.8%) were common. Each 1 °C increase in ambient temperature was associated with lower odds of vitamin D deficiency (aOR 0.970, Conclusion: Ambient temperature emerged as the primary meteorological factor associated with maternal vitamin status. Both deficiency and excess were associated with adverse delivery and neonatal outcomes, supporting the need for population-specific optimization beyond deficiency prevention.