Research: Vitamin D levels during pregnancy could impact birth weight

CHEVY CHASE, Md. — Vitamin D levels in women during pregnancy could impact birth weight, according to research released Tuesday by the Endocrine Society.

“We found that a mother’s vitamin D level, in the first or second trimester of pregnancy, was related to the normal growth of babies who delivered at term,” stated Alison Gernand of the University of Pittsburgh and lead author of the study. “If a mother was vitamin D-deficient, the birth weight of her baby was 46 g lower after accounting for other characteristics of the mom. Also, if moms were vitamin D-deficient in the first trimester, they had twice the risk of delivering a baby that suffered from growth restriction during the pregnancy.”

The major source of vitamin D for children and adults is exposure to natural sunlight. Very few foods naturally contain or are fortified with vitamin D. Thus, the major cause of vitamin D deficiency is inadequate exposure to sunlight. Vitamin D deficiency can result in abnormalities in calcium, phosphorus and bone metabolism, and there has been recent interest in understanding the role of vitamin D in other health conditions. Previous studies have shown inconsistent associations between maternal vitamin D status and fetal size.

The study has been accepted for publication in The Endocrine Society’s Journal of Clinical Endocrinology & Metabolism.