Preterm birth trends in the United States post aspirin recommendation guidelines
Recommended Citation
Ayyash MK, Al-Kouatly HB, Shaman M, and McLaren RA, Jr. Preterm birth trends in the United States post aspirin recommendation guidelines. J Natl Med Assoc 2025.
Document Type
Article
Publication Date
8-22-2025
Publication Title
Journal of the National Medical Association
Abstract
OBJECTIVES: To evaluate changes in preterm birth (PTB) rates in the U.S. following the United States Preventive Services Task Force (USPSTF) aspirin recommendation guidelines.
METHODS: A retrospective cohort study was conducted using the US Natality database. The pre-aspirin (pre-ASA) group included births from 2010-2014, while the post-aspirin (post-ASA) group included births from 2016-2021. Births from 2015, the guideline publication year, were excluded. Outcomes were overall PTB rates (< 37 weeks) and early PTB rates (< 34 weeks). Univariable and multivariable analyses were performed. Projected trends based on 2010-2014 data were compared to observed trends post-guideline implementation to assess differences.
RESULTS: The pre-ASA group included 12.1 million births, and the post-ASA group included 17.6 million. Adjusted analyses showed lower PTB rates in the post-ASA group: < 37 weeks (8.4 % vs 8.8 %; aOR 0.940 [0.937-0.944]) and < 34 weeks (2.3 % vs 2.4 %; aOR 0.92 [0.910-0.923]). However, observed post-ASA trends closely followed projected trends until 2021, when PTB rates exceeded projections.
CONCLUSION: Although adjusted analyses suggest modest reductions in PTB following USPSTF aspirin guidelines, observed trends did not show a clear reduction following aspirin implementation.
Medical Subject Headings
Aspirin; Birth; Preeclampsia; Preterm; Trends
PubMed ID
40849217
ePublication
ePub ahead of print
