Infants of women who are normal weight prepregnancy have the lowest total infant, neonatal, and postneonatal mortality rates, with increased rates seen for infants of women who are underweight or who have obesity prepregnancy, according to the Aug. 21 National Vital Statistics Reports, a publication from the U.S. Centers for Disease Control and Prevention.
Danielle M. Ely, Ph.D., from the National Center for Health Statistics in Hyattsville, Maryland, and colleagues present 2017 to 2018 infant mortality rates in the United States by maternal and infant characteristics.
The researchers found that infants of women who were normal weight prepregnancy had the lowest total infant, neonatal, and postneonatal mortality rates, which increased with increasing prepregnancy body mass index. Compared with infants of women who were normal or overweight before pregnancy, infants of women who were underweight prepregnancy had higher total, neonatal, and postneonatal mortality rates. Compared with infants born to women with obesity, mortality rates were generally, but not exclusively, higher for infants of underweight women. For all maternal age and race and Hispanic-origin groups, infants born to women of normal weight generally had lower mortality rates than infants born to women with obesity prepregnancy.
“Nonoptimal body mass index before pregnancy has implications for infant and maternal health, given the potential for adverse health outcomes for both women and infants,” the authors write.