Institutional members access full text with Ovid®

Share this article on:

Trends in Childbirth Before 39 Weeks’ Gestation Without Medical Indication

Kozhimannil, Katy B. PhD, MPA*; Macheras, Michelle MA; Lorch, Scott A. MD, MSCE

doi: 10.1097/MLR.0000000000000153
Original Articles

Background: There is increasing attention to labor induction and cesarean delivery occurring at 37 0/7–38 6/7 weeks’ gestation (early-term) without medical indication.

Objective: To measure prevalence, change over time, patient characteristics, and infant outcomes associated with early-term nonindicated births.

Research Design and Subjects: Retrospective analysis using linked hospital discharge and birth certificate data for the 7,296,363 uncomplicated births (>37 0/7 wk’ gestation) between 1995 and 2009 in 3 states.

Measures: Early-term nonindicated birth is calculated using diagnosis codes and birth certificate records. Secondary outcomes included infant prolonged length of stay and respiratory distress.

Results: Across uncomplicated term births, the early-term nonindicated birth rate was 3.18%. After adjustment, the risk of nonindicated birth before 39 0/7 weeks was 86% higher in 2009 than in 1995 [hazard ratio (HR)=1.86; 95% confidence interval (CI), 1.81–1.90], peaking in 2006 (HR=2.03; P<0.001). Factors independently associated with higher odds included maternal age, higher education levels, private health insurance, and delivering at smaller-volume or nonteaching hospitals. Black women had higher risk of nonindicated cesarean birth (HR=1.29; 95% CI, 1.27–1.32), which was associated with greater odds of prolonged length of stay [adjusted odds ratio (AOR)=1.60; 95% CI, 1.57–1.64] and infant respiratory distress (AOR=2.44; 95% CI, 2.37–2.50) compared with births after 38 6/7 weeks. Early-term nonindicated induction was also associated with comparatively greater odds of prolonged length of stay (AOR=1.20; 95% CI, 1.17–1.23).

Conclusions: Nearly 4% of all uncomplicated births to term infants occurred before 39 0/7 weeks’ gestation without medical indication. These births were associated with adverse infant outcomes.

*Division of Health Policy and Management, University of Minnesota School of Public Health, Minneapolis, MN

Children’s Hospital of Philadelphia, Philadelphia, PA

Supplemental Digital Content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal's Website, www.lww-medicalcare.com.

Supported by the University of Minnesota’s Building Interdisciplinary Research Careers in Women’s Health (BIRCWH) Program (5K12HD055887) funded through a grant from the Eunice Kennedy Shriver National Institute for Child Health and Human Development (NICHD) and R01 HS018661 funded by the Agency for Healthcare Research and Quality (AHRQ). The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health or the Agency for Healthcare Research and Quality.

The authors declare no conflict of interest.

Reprints: Katy B. Kozhimannil, PhD, MPA, Division of Health Policy and Management, University of Minnesota School of Public Health, 420 Delaware St SE, MMC 729, Minneapolis, MN 55455. E-mail: kbk@umn.edu.

© 2014 by Lippincott Williams & Wilkins.