Nutritional control of fetal growth.
Maternal micronutrient nutrition is an important determinant of size and body composition of the fetus. Maternal iron, iodine, calcium, folate, vitamin A, and vitamin C nutrition all influence offspring size. The Pune Maternal Nutrition Study was designed to study the relationship between maternal nutrition and fetal growth, size at birth, and postnatal growth. Maternal circulating folate and vitamin C concentrations predicted larger offspring size, while higher ferritin levels predicted smaller-sized babies. Subclinical vitamin B12 deficiency is common in India, especially in vegetarians, and children born to mothers with the lowest vitamin B12 but the highest folate status were the most adipose and the most insulin resistant. Furthermore, the relationship between maternal nutrition, fetal growth, and risk of type 2 diabetes and coronary heart disease appears to be much more complex than the simplistic postulates of the "fetal origins" hypothesis.