The incidence of poor fetal growth (both low birth weight (LBW) and intrauterine growth retardation (IUGR)) is quite high in developing countries and in India. A number of surveys have confirmed a high rate of LBW, IUGR and other poor maternal and infant outcomes in India. World Health Organization (WHO) has also estimated a high incidence of ~ 28.3% LBW in South Central Asia. Since the majority of LBW infants in India and most developing countries are a result of IUGR, studies that explore the etiology of IUGR and interventions aimed at preventing fetal growth retardation are urgently needed. The cause of LBW is multi-factorial, and number of nutrient has critical roles in contributing to an optimal birth outcome. Along with various maternal parameters such as pre-pregnancy weight, gestational weight gain, morbidity during pregnancy and various pregnancy risk factors, nutrition plays an important role in determining birth outcomes.

In recent past studies have shown birth size to be strongly associated with antenatal consumption of green leafy vegetables and fruits. Similarly dairy and meat protein are also known to be related to birth weight, specifically milk intake during pregnancy. Results from our laboratory have shown that vitamin maternal B₁₂ is also a strong determinant of IUGR. Since vitamin B₁₂ is necessary for methyl group production, hence methylation reactions, it plays an important role in facilitating the reactions by incorporating and transferring the methyl groups through the methionine transmethylation pathway. The mechanism by which vitamin B₁₂ deficiency may operate is thought to be through epigenetic phenomena relating to the lower methylation of key regions of the genome which can be examined in placental specimens. There is a need for studies that look for mechanisms relating to these observations above through rational but scalable intervention strategies. Some policy makers have prematurely called for the initiation of micronutrient supplementation in the absence of data that evaluate the (mechanistic) relationship between these potential micronutrient deficiencies and adverse pregnancy outcome. It is important to investigate the mechanisms involved in relationships of micronutrients and adverse birth outcomes as evidences from retrospective studies have shown an increased risk for chronic metabolic and cardiovascular disease in adulthood with an inverse relationship to birth weight. To take these findings forward into practice, carefully controlled intervention trials are needed, and there are no satisfactory data in the literature. Therefore we plan to study the effect of protein intake and protein with vitamin B₁₂ intake during pregnancy and epigenetic mechanisms of vitamin B₁₂ involved during pregnancy.