Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2016 Jul 26;316(4):410-9.
doi: 10.1001/jama.2016.9635.

Temporal Trends in Late Preterm and Early Term Birth Rates in 6 High-Income Countries in North America and Europe and Association With Clinician-Initiated Obstetric Interventions

Jennifer L Richards  1 , Michael S Kramer  2 , Paromita Deb-Rinker  3 , Jocelyn Rouleau  3 , Laust Mortensen  4 , Mika Gissler  5 , Nils-Halvdan Morken  6 , Rolv Skjærven  7 , Sven Cnattingius  8 , Stefan Johansson  8 , Marie Delnord  9 , Siobhan M Dolan  10 , Naho Morisaki  11 , Suzanne Tough  12 , Jennifer Zeitlin  9 , Michael R Kramer  1
Affiliations

Temporal Trends in Late Preterm and Early Term Birth Rates in 6 High-Income Countries in North America and Europe and Association With Clinician-Initiated Obstetric Interventions

Jennifer L Richards et al. JAMA. .

Erratum in

  • Data Error in Figure.
    [No authors listed] [No authors listed] JAMA. 2016 Oct 18;316(15):1601. doi: 10.1001/jama.2016.14786. JAMA. 2016. PMID: 27755617 No abstract available.

Abstract

Importance: Clinicians have been urged to delay the use of obstetric interventions (eg, labor induction, cesarean delivery) until 39 weeks or later in the absence of maternal or fetal indications for intervention.

Objective: To describe recent trends in late preterm and early term birth rates in 6 high-income countries and assess association with use of clinician-initiated obstetric interventions.

Design: Retrospective analysis of singleton live births from 2006 to the latest available year (ranging from 2010 to 2015) in Canada, Denmark, Finland, Norway, Sweden, and the United States.

Exposures: Use of clinician-initiated obstetric intervention (either labor induction or prelabor cesarean delivery) during delivery.

Main outcomes and measures: Annual country-specific late preterm (34-36 weeks) and early term (37-38 weeks) birth rates.

Results: The study population included 2,415,432 Canadian births in 2006-2014 (4.8% late preterm; 25.3% early term); 305,947 Danish births in 2006-2010 (3.6% late preterm; 18.8% early term); 571,937 Finnish births in 2006-2015 (3.3% late preterm; 16.8% early term); 468,954 Norwegian births in 2006-2013 (3.8% late preterm; 17.2% early term); 737,754 Swedish births in 2006-2012 (3.6% late preterm; 18.7% early term); and 25,788,558 US births in 2006-2014 (6.0% late preterm; 26.9% early term). Late preterm birth rates decreased in Norway (3.9% to 3.5%) and the United States (6.8% to 5.7%). Early term birth rates decreased in Norway (17.6% to 16.8%), Sweden (19.4% to 18.5%), and the United States (30.2% to 24.4%). In the United States, early term birth rates decreased from 33.0% in 2006 to 21.1% in 2014 among births with clinician-initiated obstetric intervention, and from 29.7% in 2006 to 27.1% in 2014 among births without clinician-initiated obstetric intervention. Rates of clinician-initiated obstetric intervention increased among late preterm births in Canada (28.0% to 37.9%), Denmark (22.2% to 25.0%), and Finland (25.1% to 38.5%), and among early term births in Denmark (38.4% to 43.8%) and Finland (29.8% to 40.1%).

Conclusions and relevance: Between 2006 and 2014, late preterm and early term birth rates decreased in the United States, and an association was observed between early term birth rates and decreasing clinician-initiated obstetric interventions. Late preterm births also decreased in Norway, and early term births decreased in Norway and Sweden. Clinician-initiated obstetric interventions increased in some countries but no association was found with rates of late preterm or early term birth.

PubMed Disclaimer

Conflict of interest statement

Conflict of Interest Disclosures: All authors have completed and submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest.

Dr Morisaki reports receiving grant funding from the Uehara Memorial Foundation, Kanzawa Medical Research Foundation, and the Danone Institute. No other disclosures were reported.

Figures

Figure
Figure. Temporal Trends in Country-Level Rates of Labor Induction, Prelabor Cesarean Delivery, and Clinician-Initiated Obstetric Intervention Among Late Preterm Births and Early Term Births, 2006–2015
For denominator data, see Table 1.
See this image and copyright information in PMC

Comment in

References

    1. Shapiro-Mendoza CK, Lackritz EM. Epidemiology of late and moderate preterm birth. Semin Fetal Neonatal Med. 2012;17(3):120–125. - PMC - PubMed
    1. The American College of Obstetricians and Gynecologists Committee on Obstetric Practice, The Society for Maternal-Fetal Medicine. Committee opinion number 561. http://www.acog.org/Resources-And-Publications/Committee-Opinions/Commit.... Accessed June 28, 2016.
    1. ACOG Committee on Practice Bulletins—Obstetrics. ACOG practice bulletin No. 107. Obstet Gynecol. 2009;114(2 Pt 1):386–397. - PubMed
    1. American College of Obstetricians and Gynecologists Committee on Obstetric Practice. ACOG committee opinion number 559. http://www.acog.org/Resources-And-Publications/Committee-Opinions/Commit.... Accessed December 15, 2015.
    1. MacDorman MF, Declercq E, Zhang J. Obstetrical intervention and the singleton preterm birth rate in the United States from 1991–2006. Am J Public Health. 2010;100(11):2241–2247. - PMC - PubMed

Publication types