(997) The Impact of ACOG's 39-Week Rule on Fetal Death Rates in America: A Systematic Review

The “39-week rule,” implemented in August 2009, strongly discouraged early term deliveries before 39 weeks without accepted ACOG 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.

Study Design:

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. In each concept, we identified keywords, subject headings, synonyms, and other related terms to exhaust search results in accordance with PRESS guidelines. We included observational studies that examined fetal death risk pre- and post-implementation of the 39-week rule. Articles were excluded if they were non-English, included non-US population, and included multiple gestations. Two blinded authors reviewed the titles (and the abstract, when necessary). The study was prospectively registered in PROSPERO.

Results:

Of 833 articles identified after initial search, 6 peer-reviewed studies met the inclusion criteria. There were 8,726 fetal deaths/7,267,648 total births (0.12%) post-implementation of the 39-week rule, and 8,523 fetal deaths/7,622,439 total births (0.11%) pre-implementation (p< 0.001) (TABLE). Compared to pre-implementation, the odds of fetal death after the 39-week rule were 1.07 (95% confidence interval 1.04-1.11).

Conclusion:

Implementation of ACOG’s 39-week rule, currently used as a quality indicator, resulted in an 7% increased risk of fetal death, compared to pre-implementation of the 39-week rule. Further study is needed to identify other unintended consequences, such as the impact on maternal and neonatal morbidity and mortality, associated with adoption of this policy.