The impact of ACOG’s 39-week rule on fetal death rates in the United States: A systematic review

•We performed a systemtic review to evluate fetal death after implementation of ACOG’s 39-week rule.•Implementation of the 39-week rule resulted in 8% increased risk of fetal death. The “39-week rule,” implemented in August 2009, strongly discouraged early term deliveries before 39 weeks without accepted ACOG delivery indications. In this study, we evaluated fetal death rates before and after the 39-week rule in the United States (US) by review of published series. Systematic literature searches were performed in PubMed, Cochrane Central Register of Controlled Trials, Embase, Cumulative Index to Nursing and Allied Health Literature, Web of Science, and Scopus databases (January 2009-June 2023). Searches were focused on the 39-week rule and fetal death. Articles were excluded if they were non-English, included non-US population, or included multiple gestations. The articles were then exported to EndNote for reference management and uploaded to Rayyan for title and abstract screening by two independent reviewers. The study was prospectively registered in PROSPERO. Of 833 articles identified after initial search, 6 peer-reviewed studies met the inclusion criteria. After combining the data from these studies, there were 8713 fetal deaths/7,294,911 total births (0.12 %) post-implementation of the 39-week rule, and 8523 fetal deaths/7,705,422 total births (0.11 %) pre-implementation. Compared to pre-implementation, the odds of fetal death after implementation of the 39-week rule were 1.08 (95 % CI 1.05–1.11). Implementation of ACOG’s 39-week rule resulted in an 8 % increased risk of fetal death compared to pre-implementation of the 39-week rule. This is alarming, but must be evaluated in the setting of decreased neonatal morbidity and mortality following the introduction of the 39-week rule.