Anemia and iron: the honest picture
Common, easily corrected, and the benefit on outcomes is unproven.
Anemia in pregnancy is common. In a US cohort of 41,226 pregnancies, 26.7% were anemic at some point. The burden is not equal: Black women had roughly 2.6 to 6.2 times the risk of anemia compared with white women depending on trimester.
Iron supplements reliably fix the blood count. Across 17 trials and 24,023 women, iron deficiency anemia at term occurred in 8.6% of supplemented women against 19.8% of controls, and iron deficiency in 46% against 70%.
What has not been shown is that this changes how mothers or babies actually do. The same review found no significant differences in quality of life, gestational diabetes, hemorrhage, hypertensive disorders, cesarean, preterm birth or birthweight. The US Preventive Services Task Force concluded that the evidence is insufficient to judge the balance of benefits and harms for either routine screening or routine supplementation.