• About Us
    • Contact Us
    • Login
    • ObGFirst
  • COVID-19
  • Alerts
  • OB
  • 2T US Atlas
  • The Genome
  • GYN
    • GYN
    • Sexual Health
  • Primary Care
  • Your Practice
  • GrandRounds
  • My Bookshelf
  • Now@ObG
  • Media
About Us Contact Us Login ObGFirst
  • COVID-19
  • Alerts
  • OB
  • 2T US Atlas
  • The Genome
  • GYN
    • GYN
    • Sexual Health
  • Primary Care
  • Your Practice
  • GrandRounds
  • My Bookshelf
  • Now@ObG
  • Media
Grand Rounds

Has the Broad Adoption of the ‘39-Week Rule’ Impacted Stillbirth and Infant Mortality Rates?

image_pdfFavoriteLoadingFavorite

BACKGROUND AND PURPOSE:

  • The ‘39-week rule’ has been instituted nationally to reduce elective deliveries <39 weeks
  • Pilliod et al. (JAMA Pediatrics, 2019) assessed the impact of the 39-week rule on stillbirths and infant deaths

METHODS:

  • Historical cohort study
  • Participants
    • Singleton, nonanomalous births
    • Between 37w0d and 42w6d
  • Data source: Birth certificates and infant death certificates
  • Groups (prior and post 39-week rule adoption)
    • Preadoption period: Births between 2008 and 2009
    • Postadoption period: Births between 2011 and 2012
  • Primary outcomes
    • Stillbirth
    • Infant death

RESULTS:

  • Preadoption: 7,322,234 births | 49.0% girls and 51.0% boys
  • Postadoption: 6,972,626 births | 49.1% girls and 50.9% boys
  • Compared to the preadoption period, in the postadoption period, there was a
    • Decrease in the proportion of deliveries at 37 weeks: −0.06%
    • Decrease in proportion of deliveries at 38 weeks: −2.5%
    • Increase in the proportion of deliveries at 39 weeks: 6.8%
    • Increase in the proportion of deliveries 40 weeks: 0.2%
  • Stillbirth rate increased in the in the postadoption cohort (P < 0.001)
    • Preadoption: 0.09%
    • Postadoption: 0.10%
    • 0.81 additional stillbirths per 10,000 pregnancies in preadoption group
  • Infant death rate decreased in the postadoption period (P < 0.001)
    • Preadoption: 0.21%
    • Postadoption: 0.20%
    • 1.37 fewer infant deaths per 10,000 live births in the postadoption group | Greatest reduction at 39 to 40 weeks
  • Overall mortality rate was not statistically different (P = .06)
    • Preadoption: 0.31%
    • Postadoption: 0.30%
  • To account for other confounders, especially older gestational age at delivery following adoption, a counterfactual model suggests that up to 34.2% of the difference in mortality could be associated with the 39-week rule

CONCLUSION:

  • Stillbirth rates increased following adoption of the 39-week rule, but infant death decreased, with an overall mortality remaining unchanged
  • Authors recognize that this study (1) Cannot account for all temporal changes in perinatal mortality over this time period and that (2) morbidity was not analyzed
  • The authors urge caution in interpreting the results of this study and suggest that

Additional investigations are warranted to examine the various contributions to the observed increased rates of stillbirth including the application of this policy and practice creep related to prolonging gestations at term among pregnancies with high-risk conditions warranting late preterm or early-term delivery


Want to be notified when new guidelines are released? Get ObGFirst! Tap Here »


Learn More – Primary Sources:

Association of Widespread Adoption of the 39-Week Rule With Overall Mortality Due to Stillbirth and Infant Death

image_pdfFavoriteLoadingFavorite
< Previous
All Grand Rounds Posts
Next >

Related ObG Topics:

Does Extending Pregnancy Beyond 39 weeks in Low-Risk Pregnancies Incur Additional Risk?
Deliver Low Risk Patients at 39 Weeks to Prevent Hypertensive Complications?
Does Elective Induction of Labor at 39 Weeks Gestation Lead to Improved Maternal and Newborn Outcomes?

Sections

  • COVID-19
  • Alerts
  • OB
  • GYN
    • GYN
    • Sexual Health
  • 2T US Atlas
  • The Genome
  • Primary Care
  • Your Practice
  • Grand Rounds
  • My Bookshelf
  • Now@ObG
  • Media

Are you an
ObG Insider?

Get specially curated clinical summaries delivered to your inbox every week for free

  • Site Map/
  • © ObG Project/
  • Terms and Conditions/
  • Privacy/
  • Contact Us/
© ObG Project
SSL Certificate


  • Already an ObGFirst Member?
    Welcome back

    Log In

    Want to sign up?
    Get guideline notifications
    CME Included

    Sign Up

Download Your ObG App
HERE!

Sign In

Lost your password?

Sign Up for ObGFirst and Stay Ahead

  • - Professional guideline notifications
  • - Daily summary of a clinically relevant
    research paper
  • - Includes 1 hour of CME every month

ObGFirst Free Trial

Already a Member of ObGFirst®?

Please log in to ObGFirst to access the 2T US Atlas

Password Trouble?

Not an ObGFirst® Member Yet?

  • - Access 2T US Atlas
  • - Guideline notifications
  • - Daily research paper summaries
  • - And lots more!
ObGFirst Free Trial

Media - Internet

Computer System Requirements

OBG Project CME requires a modern web browser (Internet Explorer 10+, Mozilla Firefox, Apple Safari, Google Chrome, Microsoft Edge). Certain educational activities may require additional software to view multimedia, presentation, or printable versions of their content. These activities will be marked as such and will provide links to the required software. That software may be: Adobe Flash, Apple QuickTime, Adobe Acrobat, Microsoft PowerPoint, Windows Media Player, or Real Networks Real One Player.

Disclosure of Unlabeled Use

This educational activity may contain discussion of published and/or investigational uses of agents that are not indicated by the FDA. The planners of this activity do not recommend the use of any agent outside of the labeled indications.

The opinions expressed in the educational activity are those of the faculty and do not necessarily represent the views of the planners. Please refer to the official prescribing information for each product for discussion of approved indications, contraindications, and warnings.

Disclaimer

Participants have an implied responsibility to use the newly acquired information to enhance patient outcomes and their own professional development. The information
presented in this activity is not meant to serve as a guideline for patient management. Any procedures, medications, or other courses of diagnosis or treatment discussed or suggested in this activity should not be used by clinicians without evaluation of their patient’s conditions and possible contraindications and/or dangers in use, review of any applicable manufacturer’s product information, and comparison with recommendations of other authorities.

Jointly provided by

NOT ENOUGH CME HOURS

It appears you don't have enough CME Hours to take this Post-Test. Feel free to buy additional CME hours or upgrade your current CME subscription plan

Subscribe

JOIN OBGFIRST AND GET CME/CE CREDITS

One of the benefits of an ObGFirst subscription is the ability to earn CME/CE credits from the ObG entries you read. Tap the button to learn more about ObGFirst

Learn More
Leaving ObG Website

You are now leaving the ObG website and on your way to PRIORITY at UCSF, an independent website. Therefore, we are not responsible for the content or availability of this site