Maternal total homocysteine concentration and neonatal size in India.

The smallness of Indian babies is ascribed to small maternal size and their chronic under nutrition. Micronutrient nutrition of the mother may be particularly important. We investigated the relationship between maternal circulating concentrations of total homocysteine (tHcy), vitamin B12 and folate and offspring size at birth. Mothers of full term small for gestation age babies (SGA, gestation and sex specific birth weight <10th centile, N = 30) and mothers of appropriate for gestational age babies (AGA, >10th centile, N = 50) were compared for their body size, plasma tHcy, vitamin B12 and red cell folate concentration at 28 week gestation. Mothers of SGA babies were lighter and shorter than those of AGA babies (P <0.05, both) and had higher plasma tHcy concentration (P<0.01). Total homocysteine concentrations were inversely related to plasma vitamin B12 and red cell folate concentrations (r = approximately -0.5, P <0.01, both). Seventy percent of the women had a low vitamin B12 status (plasma vitamin B12 <150 pmol/L) but none were folate deficient (red cell folate <283 nmol/L). Higher maternal plasma tHcy concentration was significantly associated with lower offspring birth weight (r = -0.28, P<0.05 adjusting for maternal height, weight, gestation at delivery and the baby's gender), this effect was reduced by adjustment for red cell folate concentration. We conclude that maternal vitamin B12 deficiency reflected in plasma tHcy concentration contributes to small size of Indian babies.