Shift in birth timing tied to decline in birth weights

Shift in birth timing tied to decline in birth weights

(HealthDay)—If rates of obstetric practices had not changed between 1990 and 2013 to include more cesarean deliveries and inductions, then the average U.S. birth weight likely would have increased over this time, according to research published online Jan. 29 in Demography.

Andrea M. Tilstra and Ryan K. Masters, Ph.D., of the University of Colorado Boulder, used restricted National Vital Statistics System data linked birth/infant death data (1990 to 2013) to analyze trends in obstetric practices, gestational age distributions, and birth weights among first-birth singletons born to U.S. non-Hispanic white, non-Hispanic black, and Latina women.

The researchers found that between 1990 and 2013, the likelihood of induced labors and increased at all gestational ages. The gestational age distribution of U.S. births significantly shifted with births much less likely to occur beyond gestational week 40 and much more likely to occur during weeks 37 to 39. Overall, births occurring at earlier gestational ages from obstetric interventions replaced nearly 18 percent of births from not-induced labor and vaginal at later gestational ages.

"Findings strongly indicate that recent declines in U.S. were due to increases in induced labor and cesarean delivery at select gestational ages," the authors write.

Explore further

US birth weights drop due to rise in cesarean births, inductions

More information: Abstract/Full Text (subscription or payment may be required)
Journal information: Demography

Copyright © 2020 HealthDay. All rights reserved.

Citation: Shift in birth timing tied to decline in birth weights (2020, March 4) retrieved 29 July 2021 from
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.

Feedback to editors

User comments