Prevalence and determinants of hypovitaminosis D in early pregnancy: a cross-sectional study among first-trimester pregnant women.

BACKGROUND: Adequate levels of vitamin D during pregnancy are essential for maintaining fetal development and reducing the risk of adverse perinatal outcomes. This study highlights the importance of improving pregnancy outcomes and promoting maternal health. It was conducted to evaluate the prevalence of serum vitamin D deficiency and its associated factors in the first trimester of pregnancy. pregnancy, given the importance of improving pregnancy outcomes and promoting maternal health. METHODS: This cross-sectional study was carried out in 2024 with 290 pregnant women in their first trimester who attended Al-Zahra and Taleghani Hospitals. Maternal data were collected using a structured questionnaire. Blood samples were obtained from participants to measure serum levels of 25-hydroxyvitamin D3 [25(OH)D]. Data analysis was performed using SPSS version 24 with statistical tests including Chi-square, Fisher's exact test, Mann-Whitney U test, Kruskal-Wallis test, and logistic regression. A p-value < 0.05 was considered statistically significant. RESULTS: The prevalence of hypovitaminosis D among pregnant women was estimated at 52.8% (95% CI: 46.98-58.54). No significant association was found between the consumption of major food groups containing vitamin D and vitamin D deficiency; however, the intake levels were generally low. Occupational status, parity of three or more, vitamin D supplementation, sun protection score, and exposure to sunlight were identified as significant predictors of vitamin D deficiency. CONCLUSION: Considering the high prevalence of hypovitaminosis D among pregnant women and its contributing factors, including vitamin D intake, sun exposure, sun protection practices, occupational status, parity greater than three, and insufficient dietary consumption of vitamin D-rich foods, there is an urgent need for nutritional education. Additionally, early prescription of vitamin D is recommended for women with hypovitaminosis D to mitigate potential adverse effects on maternal and fetal health.