Survey on serum vitamin D concentration, nutrient intake, and sun exposure in pregnant women (second trimester of pregnancy)

Abstract

Serum vitamin D deficiency in pregnant women increases the risk of perinatal abnormalities. Serum vitamin D is obtained from food as a nutrient and synthesized by the body upon exposure to sunlight. The purpose of this study was to investigate relationships between serum vitamin D level in pregnant women with nutrient intake, ingestion of vitamin D-rich foods and sun exposure. The study subjects were 24 pregnant women in the second trimester, who were divided into two groups according to their serum 25-hydroxy vitamin D concentrations: vitamin D deficient group (less than 20 ng/mL, n = 15) and non-deficient group (20 ng/mL or more, n = 9). Serum 25-hydroxy vitamin D concentrations were 15.2 ± 3.1 ng/mL in the deficient group and 25.4 ± 3.7 ng/mL in the non-deficient group. There were not any differences in the intakes of nutrients and vitamin D-rich foods between the two groups. By contrast, a difference was observed in the percentage of the subjects exposed to sunlight for at least 60 minutes per week: 100% in the non-deficient group, 60% in the deficient group (p = 0.052). To prevent vitamin D deficiency in pregnant women, nutritional education to increase vitamin D intake from food and lifestyle modification program to increase vitamin D synthesis are recommended.