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, p < 0.001) and vitamin A deficiency (aOR 0.976, p = 0.008), with significant temperature–humidity and temperature–wind interactions ( p < 0.001). Vitamin A deficiency was associated with higher odds of PROM (aOR 1.76, 95% CI 1.44–2.14), whereas low or moderate vitamin D and A levels were associated with lower odds of fetal distress and meconium staining (aOR approximately 0.85, p < 0.05). Vitamin A deficiency was associated with markedly higher odds of macrosomia (aOR 3.14), and vitamin E excess was associated with a 60% increase in odds (aOR 1.60). Restricted cubic spline models revealed U-shaped associations between vitamin A and low birth weight, and between vitamin D and macrosomia. 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.