Maternal anemia and underweight as determinants of pregnancy outcomes: cohort study in eastern rural Maharashtra, India.

Objectives To study the trend in the prevalence of anaemia and low BMI among pregnant women from Eastern Maharashtra and evaluate if low BMI and anaemia affect pregnancy outcomes. Design Prospective observational cohort study. Setting Catchment areas of 20 rural primary health centres in four eastern districts of Maharashtra State, India. Participants 72750 women from the Nagpur site of Maternal and Newborn Health Registry of NIH's Global Network, enrolled from 2009 to 2016. Main outcome measures Mode of delivery, pregnancy related complications at delivery, stillbirths, neonatal deaths and low birth weight (LBW) in babies. Results Over 90% of the women included in the study were anaemic and over a third were underweight (BMI <18kg/m2) and with both conditions. Mild anaemia at any time during delivery significantly increased the risk (Risk ratio; 95% confidence interval (RR;(95%CI)) of stillbirth (1.3 (1.1-1.6)), neonatal deaths (1.3 (1-1.6)) and LBW babies (1.1 (1-1.2)). The risks became even more significant and increased further with moderate/severe anaemia any time during pregnancy for stillbirth (1.4 (1.2-1.8)), neonatal deaths (1.7 (1.3-2.1)) and LBW babies (1.3 (1.2-1.4)).,. Underweight at anytime during pregnancy increased the risk of neonatal deaths (1.1 (1-1.3)) and LBW babies (1.2;(1.2-1.3)). The risk of having stillbirths (1.5;(1.2-1.8)), neonatal deaths (1.7;(1.3-2.3)) and LBW babies (1.5;(1.4-1.6)) was highest when - the anaemia and underweight co-existed in the included women. Obesity/overweight during pregnancy increased the risk of maternal complications at delivery (1.6;(1.5-1.7)) and of caesarean section (1.5;(1.4-1.6)) and reduced the risk of LBW babies 0.8 (0.8-0.9)). Conclusion Maternal anaemia is associated with enhanced risk of stillbirth, neonatal deaths and LBW. The risks increased if anaemia and underweight were present simultaneously. Trial registration number NCT01073475.