Vitamin D Status Among Pregnant and Breastfeeding Women: A Cross-Sectional Study

Abstract

Vitamin D deficiency has consistently been reported among women during pregnancy and lactation, although findings regarding the prevalence of deficiency and associated risk factors vary considerably. This cross-sectional study investigated the vitamin D status of a convenience sample of pregnant women and breastfeeding mothers in southern Brazil, and it identified potential factors related to vitamin D deficiency. After excluding women who did not meet the eligibility criteria, the final study population comprised 152 women, categorized into three groups: first-trimester pregnant women (n = 35), second-trimester pregnant women (n = 45), and breastfeeding mothers of infants under six months of age (n = 72). A vitamin D deficiency rate of 34.2% was observed, with the deficiency rate being significantly lower among first-trimester pregnant women compared with breastfeeding mothers and second-trimester pregnant women. Older age and lower milk consumption were identified as independent risk factors for vitamin D deficiency. Seasonal variation in vitamin D status was also evident, with higher serum 25-hydroxyvitamin D concentrations and lower deficiency rates recorded during the summer months. The results suggest that pregnant women and breastfeeding mothers are at risk of vitamin D deficiency even in a region with high solar irradiation. Screening for vitamin D status and supplementation initiatives should therefore be considered, especially during the winter months (Shrestha et al., 2021) ; (Maghbooli et al., 2007).

Observational studies in various parts of the world have reported alarming rates of vitamin D deficiency and insufficiency among pregnant and postpartum women (Kareem Mohammed, 2023).