USPSTF: Still not enough evidence to recommend iron supplementation during pregnancy

Key takeaways:

• The USPSTF found no differences in iron supplementation vs. placebo or no iron for several conditions during pregnancy.
• The task force also called for more evidence on the benefits and harms of screening.

There is inadequate evidence to recommend for or against the use of iron supplements during pregnancy or screening pregnant people for iron deficiency and iron deficiency anemia, according to the U.S. Preventive Services Task Force.

In its draft recommendation published Tuesday, the task force issued I statements — which are given when not enough evidence is available to support a preventive service or the evidence is poor or conflicting. It is the same position the USPSTF took in its 2015 final recommendation on screening for iron deficiency anemia in pregnant people.

“Iron is a nutrient that is important to overall health, especially during pregnancy,” USPSTF member Esa Davis, MD, MPH, said in a press release. “The challenge is that we don’t have the evidence to tell us whether or not screening and supplementation improve the health of mothers and their babies, so we are calling for more research on these important topics.”

According to the task force, all pregnant people are at an increased risk for developing iron deficiency and iron deficiency anemia because they need more iron during pregnancy.

The USPSTF added that Black and Mexican American patients have higher rates of iron deficiency anemia during pregnancy. Other factors that can increase the risk include:

• conditions or medications that reduce iron absorption;
• diets low in iron-rich foods; and
• short intervals between pregnancies.

In the draft evidence report, Amy Cantor, MD, MPH, an associate professor of family medicine at the Oregon Health & Science University School of Medicine, and colleagues reviewed 17 studies on the impact of routine iron supplementation.

They found prenatal iron supplementation resulted in no significant differences in rates of gestational diabetes, cesarean deliveries or maternal hemorrhage compared with placebo or no iron supplementation, nor did it improve maternal quality of life.

Additionally, there were no studies on the harms or benefits of screening for iron deficiency and iron deficiency anemia in pregnant people.

The USPSTF noted that the recommendation is only for people who show no signs or symptoms of iron deficiency.

“We need more evidence on the effectiveness of screening for iron deficiency and the use of iron supplements in pregnant people without signs or symptoms of anemia,” task force member David Chelmow, MD, said in the release. “Prenatal care is important. In the absence of clear evidence, health care professionals should use their judgment when recommending whether their pregnant patients should be screened or take iron supplements.”

References:

• Iron deficiency anemia in pregnant women: Screening and supplementation. https://www.uspreventiveservicestaskforce.org/uspstf/recommendation/iron-deficiency-anemia-in-pregnant-women-screening-and-supplementation. Published Sept. 7, 2015. Accessed Feb. 21, 2024.
• U.S. Preventive Services Task Force issues draft recommendation statement on screening and supplementation for iron deficiency during pregnancy. https://www.uspreventiveservicestaskforce.org/uspstf/sites/default/files/file/supporting_documents/iron-deficiency-anemia-screening-pregnancy-draft-rec-news-bulletin.pdf. Published Feb. 27, 2024. Accessed Feb. 27, 2024.
• U.S. Preventive Services Task Force. Identifying evidence gaps. https://www.uspreventiveservicestaskforce.org/uspstf/about-uspstf/methods-and-processes/identifying-evidence-gaps. Accessed Feb. 26, 2024.
• Screening and supplementation for iron deficiency and iron deficiency anemia during pregnancy: Systematic review to update the U.S. Preventive Services Task Force recommendation. https://www.uspreventiveservicestaskforce.org/uspstf/document/draft-evidence-review/iron-deficiency-anemia-during-pregnancy-screening-supplementation. Accessed Feb. 27, 2024.
• Screening and supplementation for iron deficiency and iron deficiency anemia during pregnancy: U.S. Preventive Services Task Force Draft recommendation statement. https://www.uspreventiveservicestaskforce.org/uspstf/draft-recommendation/iron-deficiency-anemia-during-pregnancy-screening-supplementation. Accessed Feb. 27, 2024.