The association between maternal anaemia and pregnancy outcomes: a cohort study in Assam, India

Objectives: To examine the association between maternal anaemia and adverse maternal and infant outcomes, and to assess the feasibility of conducting epidemiological studies through the Indian Obstetric Surveillance System–Assam (IndOSS-Assam) Design: Retrospective cohort study using anonymised hospital records. Exposure: maternal iron deficiency anaemia; outcomes: postpartum haemorrhage (PPH), low birthweight, small-for-gestational age, perinatal death. Setting: Five government medical colleges in Assam. Study population: 1007 pregnant women who delivered in the five medical colleges from January to June 2015. Main outcome measures: Odds ratios with 95% confidence intervals (CI) to estimate the association between maternal iron deficiency anaemia and the adverse maternal and infant outcomes. Potential interactive roles of infections and induction of labour on the adverse outcomes were explored. Results: 35% (n=351) pregnant women had moderate-severe anaemia. Women with severe anaemia had a higher odds of PPH (adjusted odds ratio (aOR)=9·45; 95%CI=2·62-34·05), giving birth to low birthweight (aOR=6·19; 95%CI=1·44-26·71) and small-for-gestational age babies (aOR=8·72; 95%CI=1·66-45·67), and perinatal death (aOR=16·42; 95%CI=4·38-61·55). Odds of PPH increased 17-fold among women with moderate-severe anaemia who underwent induction of labour and increased 19-fold among women who had infection and moderate-severe anaemia. Conclusion: Maternal iron deficiency anaemia is a major public health problem in Assam. Maternal anaemia was associated with increased risks of PPH, low birthweight, small-for-gestational age babies and perinatal death. While the best approach is prevention a large number of women present with severe anaemia late in pregnancy and there is no clear guidance on how these women should be managed during labour and delivery