Abstract

Introduction: Vitamin D is classically involved in the regulation of calcium and phosphate homeostasis. It is increasingly being recognized to have a multitude of effects on various cell systems and signaling pathways. Vitamin D level of the mother during pregnancy is also assuming great importance as it is expected to have the potential to influence the birth weight.

Objectives: To identify associations between maternal vitamin D deficiency and risk of low birth weight among term newborns and evaluate the socio-demographic factors associated with it.

Material and Methods: A case control study was carried out in the Neonatal Division, JNMCH, during September 2016 to August 2018. Mothers (n=208) were divided into two groups with newborns birth weight <2.5 kg (cases) and 2.5 kg or more (controls). Maternal socio-demographic history and anthropometric examinations of the newborns were noted in a proforma. Maternal vitamin D levels were estimated. Maternal vitamin D statuses of both groups were compared. Analysis was done by SPSS 25.

Results: Mean vitamin D level in mothers of LBW (Low Birth Weight) new-borns (Cases) 12.375 ± 4.20 ng/mL while in mothers of normal birth weight new-borns (Controls) was 16.987 ± 6.38 ng/mL and there is statistically significant correlation between maternal vitamin D and birth weight of term newborns (p<0.01). Also there is positive correlation between maternal vitamin D status and residence, calcium supplementation, seasonal variation, daily sun exposure and shows no correlation with maternal age, educational qualification, parity of mother, BMI and occupation of mothers.

Conclusions: We found high prevalence of hypovitaminosis D in mothers. Low vitamin D levels were significantly associated with LBW and it was found to be associated with certain modifiable and non-modifiable risk factors. There is a need for recommendation for vitamin D supplementation during pregnancy.

Keywords: Pregnancy; Newborns; Birth weight; Vitamin D status; Socio-demographic status