Estimating serum vitamin D levels and assessing its influencing factors among antenatal women in a South Indian town-Kumbakonam urban rural epidemiological study: KURES-5

Background: Adequate antenatal Vitamin D intake is essential for maternal and fetal health during pregnancy and avoidance of adverse outcomes. The normal and abnormal concentrations are not well established in the different parts of the world with varying customs in life. We intended to estimate the normal random serum Vitamin D levels among antenatal mothers in the first trimester and whether factors such as age, weight, and religion have any influence on the same. Materials and Methods: In this epidemiological study of 644 parturients, we collected the blood samples from asymptomatic antenatal mothers in the first trimester. A simple convenient sample of mothers on no other supplements except folate was selected. The present study was done from April 2019 to March 2020 after individual informed consent and ethical clearance. The factors such as age, weight, type of diet, occupation, and religion were noted. The estimation of Vitamin D3 levels was done by the well described chemiluminescent technique. A value of <20 ng/ml was defined as deficient. Student t-tests, analysis of variance, and correlation tests were done accordingly to find out the influence of the above factors on the level. Results: 83.7% of all women were deficient in Vitamin D3, if the level of 20 ng/ml was taken as cutoff. The mean Vitamin D3 level was 14.57 ± 6.73 ng/ml. Religion wise, the mean Vitamin D3 was 16.63 ng/ml in Hindus (sample – 402/644), 10.55 ng/ml in Muslims (sample – 207/644), 14.27 ng/ml in Christians (sample – 16/644), and 15.08 ng/ml in others (sample – 19/644). There was a significant reduction in the levels of Vitamin D in Muslim women. There is no influence of age, weight, or dietary pattern. Conclusion: A majority of Indian pregnant women were deficient in Vitamin D3, worse among Muslims. We conclude that lifestyle changes with more exposure to sunlight should be suggested to all women in the reproductive age group to circumvent the problem. Health education on these lines should be imparted to them.