Comparison of sun exposure versus vitamin D supplementation for pregnant women with vitamin D deficiency

Abstract

Introduction: Maternal vitamin D deficiency is widespread health problem that is more important in pregnant women, which affects fetus growth and bone development. The aim of this study was to evaluate the effect of sun exposure versus vitamin D supplementation for pregnant women with vitamin D deficiency.

Materials and methods: This prospective clinical trial was performed on 87 pregnant women with vitamin D deficiency. Group A was treated with vitamin D 4000 IU per day for 10 weeks, while group B was recommended for sun exposure for 30 minutes daily (30% body surface area) for 10 weeks in summer and between 10 am-4 pm in direct sunlight. After the delivery, 25-hydroxyvitamin D₃ levels were measured in the same previous center. Moreover, weight, height, and head circumference of fetus were measured at delivery in both groups and compared with each other.

Results: After 10-week intervention, 25-hydroxyvitamin D₃ levels was significantly higher in group treated with vitamin D as compared to sun expose group (31.27 versus 19.79 ng/ml). (p < .001). However, height (p = .118), weight (p = .245), and head circumference (p = .681) of infants in both groups did not show significant differences.

Conclusions: Vitamin D supplementation is more effective than sun exposure in increasing 25-hydroxyvitamin D₃ in pregnant women with vitamin D deficiency.

Keywords: 25-hydroxyvitamin D; Sunlight exposure; vitamin D deficiency.