BACKGROUND AND PURPOSE:

• Haavaldsen et al. (Acta Obstetricia et Gynecologica Scandinavica, 2022) assess whether changes in prevalence of labor induction in gestational weeks 37 to 42 weeks were accompanied by changes in adverse pregnancy outcomes or mode of delivery

METHODS:

• Retrospective population study
  • Data from the Medical Birth Registry of Norway
  • 1999 through 2019
• Population
  • All singleton births
  • Gestational weeks 37 to 42
• Exposure
  • Year of study
  • Gestational week at birth
• Primary outcome
  • Labor induction and outcome measures

RESULTS:

• 1,127,945 pregnancies
• Over the study period, the prevalence of labor induction increased from 9.7% to 25.9%
  • This increase was particularly high in gestational week 41
• There was a modest decline in fetal deaths observed for all gestational weeks, except gestational week 41
  • Overall decline
    • 1999 to 2004: 0.18% decline
    • 2015 to 2019: 0.13% decline
• There were no overall changes in other perinatal outcomes
• The prevalence of postpartum hemorrhage ≥500 ml increased
  • 1999: 11.4%
  • 2019: 30.1%
• Operative deliveries also increased slightly
• The prevalence of acute cesarean section increased
  • 1999: 6.5%
  • 2019: 9.3%
• The prevalence of vacuum and/or forceps assisted deliveries also increased
  • 1999: 7.8%
  • 2019: 10.4%

CONCLUSION:

• Between 1999 and 2019 there was an increase in the number of inductions, but only a modest decline in perinatal deaths, and no decline in other adverse outcomes
• The increase in inductions was primarily at 41 weeks, due to change in guidelines in 2010
• The authors state

Our study suggests that routine induction of labor in all ongoing pregnancies in gestational week 41 would not result in significantly better outcomes 

Learn More – Primary Sources:

Is the increasing prevalence of labor induction accompanied by changes in pregnancy outcomes? An observational study of all singleton births at gestational weeks 37–42 in Norway during 1999–2019

Related ObG Topics:

Does Elective Induction of Labor at 39 Weeks Gestation Lead to Improved Maternal and Newborn Outcomes?

Labor Induction and an Unripe Cervix: Does it Result in More C-sections?

Induction vs Expectant Management At and Beyond Term – the Cochrane Review

Is There a Link between Induction of Labor and Cesarean Delivery?