Rate of preterm births rises nationally after years of decline

Infants who are born preterm face significant risks in survival, growth and development, a public health concern that prompted a national awareness and prevention movement in 2005. Today, the preterm birth rate after nearly a decade of steady decreases has been inching up again, according to a clinical report published by the American Academy of Pediatrics in the November 2019 Pediatrics.

Dan Stewart, MD, professor of pediatrics at the University of Louisville, is a lead author of the report and practices with UofL Physicians – Neonatology. Co-authors are members of the AAP’s Committee on Fetus and Newborn.

The report, “Updates on an At-Risk Population: Late Preterm and Early Term Infants” (published online Oct. 21), defines the sub-categories of preterm births and reports an increase in the preterm birth rate that began in 2015.

The preterm birth rate reached its lowest level in a decade of 9.57 percent in 2014 but rose to 9.97 percent by 2018. The trend is largely attributed to increases in the rate of late preterm births, defined as those infants born between 34 weeks’ gestation and 36 weeks, 6 days’ gestation, predominately among black and Hispanic women.

Late preterm births account for approximately 70 percent of all preterm births in the U.S., and they account for 7 percent of all live births. Early term births, defined as those occurring between 37 weeks’ gestation and 38 weeks, 6 days’ gestation, also pose significant risks to an infant.

“We recommend continued use of population data to help monitor the rates of preterm births for trends, changes in practice and need for interventions,” Stewart said. “Other recommendations include planning with obstetric providers to improve the understanding of the causes of and risks for late preterm and early term deliveries.”