Research in context
anaemia, deaths, death, Anaemia
ANAEMIA, POSTPARTUM HAEMORRHAGE, ANAEMIA

A systematic review and meta-analysis of the association between prenatal anaemia and postpartum haemorrhage was published in 2019. The review reported the results of a search of MEDLINE, Scopus, 
To our knowledge, this is the first study to examine the association between prebirth haemoglobin and postpartum haemorrhage, with haemoglobin as a continuous variable. This was possible because of the large sample size (n=10 561). The study participants were from low-income and middle-income countries where almost all deaths from postpartum haemorrhage occur. We controlled for confounding factors and there were negligible missing data. We found that with decreasing maternal haemoglobin concentration, the risk of postpartum haemorrhage increases monotonically. A 10 g/L decrease in prebirth haemoglobin is associated with increased odds for clinician-diagnosed postpartum haemorrhage. Women with severe anaemia had seven-fold increased odds of death or near miss compared with women with moderate anaemia. Our results were robust to different definitions of postpartum haemorrhage and to correction for haemoglobin measurement error.
Anaemia is strongly associated with postpartum haemorrhage, with a dose–response relationship. Anaemia also increases the risk of death from postpartum haemorrhage and near miss. Attention should be given to preventing and treating anaemia in women of reproductive age.