- •Studies evaluating thresholds to define anemia in a contemporary pregnant population are lacking.
- •The optimal hemoglobin to reduce the need for transfusion at delivery has not been well defined.
- •B. What are the key findings?
- •Maternal anemia before delivery was associated with 5-fold higher odds of pRBC transfusion, as well as higher odds of postpartum readmission and longer postpartum hospitalization.
- •For each 1 g/dL increase in pre-delivery hemoglobin, the odds of transfusion were 56% lower.
- •We identified an optimal pre-delivery hemoglobin of ≥10.6 g/dL to predict peripartum transfusion.
- •C. What does this study add to what is already known?
- •The optimal hemoglobin (10.6 g/dL) for predicting transfusion is similar to the previously identified threshold for anemia endorsed by ACOG (10.5 g/L in the second trimester and 11.0 g/dL in the third trimester).
- •Pre-delivery anemia is associated with higher odds of several adverse maternal outcomes but not neonatal outcomes.
- •Anemia optimization may be primarily for maternal benefit and should be evaluated in prospective studies.
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Publication stageIn Press Accepted Manuscript
This was presented as a poster (ID #889) at the 42nd annual Society of Maternal Fetal Medicine conference February 4, 2022.