A six-year study of nearly 100,000 women in Botswana has provided evidence suggesting relatively inexpensive daily diet supplementation with iron, folic acid and vitamins during pregnancy can reduce complications at birth.
Researchers found both iron and folic acid supplementation (IFAS), as well as iron and folic acid plus essential vitamins and trace minerals (multiple micronutrient supplementation, or MMS), were associated with significantly lower rates of babies born at low birthweight and other complications at birth, compared to iron or folic acid alone. For example, the rate of low-birthweight birth was under 10.5% for women supplementing their diets with multiple micronutrients, the lowest rate of any comparison group.
Published in Lancet Global Health, the study was led by Ellen Caniglia, ScD, an assistant professor of Epidemiology in the Department of Biostatistics, Epidemiology, and Informatics at the Perelman School of Medicine at the University of Pennsylvania, as well as investigators at the Botswana-Harvard AIDS Institute Partnership and Harvard T.H. Chan School of Public Health. The study also included a substantial cohort of pregnant women with HIV, and found IFAS and MMS appeared to have even larger benefits in this group.
Caniglia and colleagues examined supplement use and birth outcomes among 96,341 women who were seen between 2014 and 2020 in a group of government hospitals in Botswana. The sample patients studied represents a large proportion of all births in Botswana in the time period. Supplement initiation was relatively easy to track in the sample because the pills were prescribed and provided free of charge by the participating hospitals. The researchers analysed how the rates of low-birthweight and other complications at birth, such as preterm or very preterm delivery, stillbirth, and neonatal death, varied according to the supplements each woman began taking during her pregnancy.
Women who initiated IFAS had clearly lower rates of most adverse birth outcomes, compared to women who took only iron or folic acid. Rates of low-birthweight births, for example, were 16.92% in the folic acid-only group and 12.70% in the iron-only group, but only 11.46% in the IFAS group.
“Our results support the current World Health Organization recommendation that pregnant women should take iron and folic acid supplementation daily, but also provide compelling evidence that multiple micronutrient supplementation has further advantages over IFAS,” Caniglia said.
To help reduce the rate of babies born at low birthweight and related complications at birth, the World Health Organization (WHO) recommends daily IFAS throughout pregnancy, in all settings, based on substantial clinical trial evidence. There is also clinical trial evidence daily prenatal MMS, which includes iron and folic acid plus vitamins and minerals/metals, may be superior to IFAS.
However, there has been a need for more evidence for MMS’s benefits, especially with respect to IFAS, in real-world settings, and in high-risk women such as women with HIV. This latest study provides evidence this approach can help.