Key TakeawaysAnemia during pregnancy increases the risk of heart defects in newbornsAnemic women have a 47% increased risk of a heart defect in their newbornIron supplementation might reduce this risk.THURSDAY, April 24, 2025 (HealthDay News) -- Treating anemia during pregnancy might lower the risk of heart defects in newborns, a new study says.Women with anemia in early pregnancy have a 47% increased risk of giving birth to a child with a heart defect, researchers reported April 23 in BJOG: An International Journal of Obstetrics & Gynecology.“We already know that the risk of congenital heart disease can be raised by a variety of factors, but these results develop our understanding of anemia specifically and take it from lab studies to the clinic,” said senior researcher Duncan Sparrow, an associate professor at the University of Oxford in the U.K.“Knowing that early maternal anemia is so damaging could be a gamechanger worldwide,” he added in a news release.For the article, researchers compared medical records of nearly 2,800 U.K. women who had a child born with a heart defect to those of nearly 14,000 women whose children were born healthy.About 4.4% of the mothers whose children had a heart defect were anemic during pregnancy, compared with 2.8% of moms with healthy children, results show.These results jibe with those from three previous studies in Israel, Canada and Taiwan that linked anemia in pregnancy with an increased risk of heart birth defects, researchers said.About two-thirds of anemia cases during pregnancy are caused by iron deficiency, researchers said.“Because iron deficiency is the root cause of many cases of anemia, widespread iron supplementation for women — both when trying for a baby and when pregnant — could help prevent congenital heart disease in many newborns before it has developed,” Sparrow said.Researchers recommended that a clinical trial be done to see if iron supplementation during pregnancy could prevent anemia and, as a result, heart defects in newborns.More informationThe Cleveland Clinic has more on anemia during pregnancy.SOURCE: Wiley, news release, April 23, 2025 .What This Means For YouPregnant women should make sure they are tested for anemia, as the condition can increase their risk of having a baby with a heart defect..Sign up for our weekly HealthDay newsletter