Prevalence of vitamin D deficiency among South Indian pregnant women.

Background: Deficiency of vitamin D is widespread across the globe. Expectant women are one of the most vulnerable groups for vitamin D deficiency (VDD). Even in South India with abundance of sunlight, pregnant women are believed to be at a high risk of this deficiency. The objectives of this study are to assess the prevalence of VDD in antenatal women, associate it with modifiable risk factors and evaluate its correlation with low birth weight. Methods: This cross-sectional study was conducted in a tertiary care hospital, in Chennai, in 100 pregnant women in their last trimester on the basis of inclusion and exclusion criteria and their vitamin D and calcium levels were assessed. A detailed history regarding physical activity, diet, and sun exposure were collected and results were analyzed. Results: The point prevalence of VDD (serum 25-hydroxyvitamin D (25(OH) D) level <20 ng/mL) among antenatal women in our study is 62%. Univariate analysis revealed that sun exposure and socioeconomic status were the significant factors associated with higher percentage of VDD. Linear regression analysis showed that only sun exposure was a significant predictor for serum 25(OH) D levels. VDD is also associated with increased risk of low-birth-weight babies. Conclusion: VDD is highly prevalent among pregnant women in South India leading to adverse health consequences in the mother and offspring. Less physical activity, decreased sun exposure, darker skin complexion, lower socioeconomic status and lack of awareness are the major risk factors associated with VDD in our study population.