Low maternal vitamin B12 status is associated with intrauterine growth retardation in urban South Indians

Objective: To assess the maternal sociodemographic, anthropometric, dietary and micronutrient status in apparently healthy pregnant women in order to determine their associations with intrauterine growth retardation ( IUGR). Design: Prospective observational study. Setting: Bangalore City, India. Subjects: A total of 478 women were recruited at 12.9 +/- 3.3 weeks of gestation and followed up at the first, second and third trimesters of pregnancy and at delivery. The dropout rate was 8.5%. Interventions: None. Main outcome measures: Birth weight was measured at hospital delivery. Results: The mean birth weight was 2.85 +/- 0.45 kg. In all, 28.6% of newborns were IUGR. There was a strong inverse relationship between maternal educational level and risk of IUGR. A low body weight at baseline was also associated with a high risk of IUGR. Compared with women in the highest quartile for second trimester weight gain, those in the lowest quartile had a significantly higher adjusted odds ratio ( AOR: 3.98; 95% CI: 1.83, 8.65) for IUGR. Women in the lowest tertile for serum vitamin B-12 concentration during each of the three trimesters of pregnancy had significantly higher risk of IUGR ( AOR: 5.98, 9.28 and 2.81 for trimesters 1 - 3, respectively). Conclusions: The present study demonstrates associations between educational status, maternal weight and gestational weight gain with IUGR. Importantly, in a subsample, there were strong associations of vitamin B-12 status with IUGR, suggesting that better socioeconomic conditions, improved nutritional status and early detection of vitamin B-12 deficiency in pregnancy combined with appropriate interventions are likely to play an important role in reducing IUGR. Sponsorship: This research was partly supported by the GlaxoSmithKline Consumer Healthcare Ltd, India.