Preterm births increasing, mostly due to cesareans

The percentage of preterm singleton births in the United States has risen to nearly 11%, with most of the increase due to higher rates of cesarean section deliveries, according to a report in the June issue of Clinics in Perinatology.

Vani R. Bettegowda, from the March of Dimes Foundation in White Plains, NY, and colleagues examined the association between CD rates and gestational age distribution among singleton live births in the US.

The researchers found that between 1996 and 2004, the proportion of preterm births increased from 9.7% to 10.7%. Most of the increase was among births delivered by C/S, with the largest increase occurring among late preterm births. Singleton C/S rates increased for all gestational ages for all maternal racial and ethnic groups, but increased at a faster rate among all preterm gestational age groups for non-Hispanic black women.

Bettegowda VR, Dias T, Davidoff MJ, et al. The relationship between cesarean delivery and gestational age among US singleton births. Clin Perinatol. 2008;35:309-323.