Maternal anemia and pregnancy outcomes: a population-based study



This study aims to describe adverse maternal and neonatal outcomes in women diagnosed with anemia in pregnancy.

Study design

This was a retrospective cohort study of California live births from 2007–2012, linked to maternal and infant hospital discharge records. Relative risks of adverse maternal and neonatal outcomes were calculated for women with and without anemia.


Anemic mothers were more likely to be diagnosed with hypertension, diabetes, placental abruption, or chorioamnionitis, or require a blood transfusion or admission to the intensive care unit (aRRs 1.2–6.8). Infants born to anemic mothers were more likely to be born preterm (8.9% versus 6.5%), but not more likely to suffer morbidities associated with prematurity.


In a population-based study, the diagnosis of anemia in pregnancy carries a higher risk of peri-partum, intra-partum, and post-partum complications for the mother, and a higher risk of preterm birth for the infant.

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The work was funded in part by the UCSF California Preterm Birth Initiative.

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Correspondence to Rachael H. Beckert.

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