Breastfeeding associated with a 33% reduction in first-year post-perinatal infant mortality

Among nearly 10 million US infants born between 2016 and 2018, breastfed babies were 33% less likely to die during the post-perinatal period (day 7−364) than infants who were not breastfed, reports a new study in the American Journal of Preventive Medicine. The findings build on previous US research with smaller datasets, which documented the association between the initiation of breastfeeding and the reduction of post-perinatal infant mortality by a range of 19% to 26%.

Lead investigator Julie L. Ware, MD, MPH, Division of General and Community Pediatrics, Department of Pediatrics, Cincinnati Children's Center for Breastfeeding Medicine, said, "Based on these data, there is clear evidence that breastfeeding confers a protective benefit during the first year of life and is strongly associated with reduced post-perinatal infant mortality across the U.S.."

Dr. Ware noted that the findings suggest there is an opportunity for breastfeeding promotion, protection, and support to be included as a key component in comprehensive infant mortality reduction initiatives in regions and states across the US.

With help from the Centers for Disease Control and Prevention (CDC) National Center for Health Statistics, birth certificate data on US infants born from 2016 to 2018 were linked with infant deaths occurring up to one year after birth. An analysis was conducted to demonstrate whether the initiation of breastfeeding, as recorded on the birth certificate (a practice adopted by all states in 2016), was associated with post-perinatal infant death, taking into account factors such maternal age, education, race and ethnicity, and geographical location.

Breastfeeding is recognized by the World Health Organization, American Academy of Pediatrics, and other authorities as the preferred normative nutrition for infants, both recommending that families breastfeed their infants exclusively for 6 months, continuing with the addition of complementary foods for at least the first 2 years of life.

These organizations consider breastfeeding a public health imperative with many short- and long-term improved health outcomes for both mother and child, including significant reductions in all-cause infant mortality and specific protection against sudden infant death syndrome and necrotizing enterocolitis in preterm infants. Despite these recommendations, the rates for breastfeeding initiation, exclusivity, and continuation in the US do not meet breastfeeding goals, especially in certain racial and ethnic populations, and in some geographic regions.

Co-investigator Ardythe Morrow, Ph.D., University of Cincinnati College of Medicine stated that, "Though breastfeeding is widely recommended, nevertheless, some may still consider it to be of minor importance. We hope that our findings will change the narrative. Human milk is replete with protective molecules, and breastfeeding offers significant protection."

Addressing breastfeeding disparities may improve the health of mothers and their babies and help reduce adverse outcomes. Although most states advocate breastfeeding promotion, protection, and support activities, analysis of the association between breastfeeding and infant mortality had not previously been conducted at the state and regional levels. To this end, the investigators conducted a regional and state-by-state analysis.

Co-investigator Aimin Chen, Ph.D., Department of Biostatistics, Epidemiology and Informatics, Perelman School of Medicine, University of Pennsylvania, explained, "We found that the effect was evident across the US, but with regional variations, ranging from 44% in the Northeast and Mid-Atlantic, where breastfeeding initiation is the highest, and 21% in the Southeast, where breastfeeding initiation is the lowest."

"Although regional and state variation in the magnitude of the association between breastfeeding and infant mortality exists, there was a remarkable consistency of reduced risk. Together with existing literature, our data suggest that breastfeeding promotion and support may be an effective strategy to help reduce infant mortality in the US."

Dr. Ware summarized, "Breastfeeding saves lives. August is National Breastfeeding Month. Let's do all we can to support breastfeeding families and improve the health of our nation."