Revisiting the basis for haemoglobin screening in pregnancy

Abstract

Purpose of review: Anaemia affects up to 50% of pregnancies worldwide, and is associated with maternal and neonatal morbidity and mortality. Prevention and management of anaemia remains a priority. Despite this, there is ongoing debate on the optimal approach to identifying anaemia in pregnant women and the best strategies for prevention and management. The objective of this review is to describe the current landscape of haemoglobin testing in pregnancy in low and high-income countries.

Recent findings: Current definitions of anaemia in pregnancy comprise a laboratory threshold of haemoglobin below which treatment is offered. Haemoglobin measurement is not sensitive in detecting iron deficiency - the most common cause of maternal anaemia. Furthermore, these historical thresholds were derived from heterogeneous populations comprising men and women. Women with anaemia in pregnancy are offered iron therapy, without testing for the underlying cause. This may be appropriate in high-income settings, where iron deficiency is the likely cause, but may not address the complex causes of anaemia in other geographical areas.

Summary: Current thresholds of haemoglobin defining anaemia in pregnancy are under review. Further research and policy should focus on optimal strategies to identify women at risk of anaemia from all causes.