Am J Perinatol
DOI: 10.1055/s-0043-1775564
Review Article

A Scoping Review of Preterm Birth Risk Factors

1   Vagelos College of Physicians and Surgeons, Columbia University, New York, New York
Daniel Mallia
2   Department of Computer Science, Hunter College, New York, New York
Qi Yan
3   Department of Obstetrics and Gynecology, Columbia University Medical Center, New York, New York
Itsik Pe'er
4   Department of Computer Science, Columbia University, New York, New York
Anita Raja
2   Department of Computer Science, Hunter College, New York, New York
Ansaf Salleb-Aouissi
4   Department of Computer Science, Columbia University, New York, New York
Ronald Wapner
3   Department of Obstetrics and Gynecology, Columbia University Medical Center, New York, New York
› Author Affiliations
Funding Research reported in this study was supported by the National Library Of Medicine of the National Institutes of Health under Award Number: R01LM013327. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.


Preterm birth is a major cause of neonatal morbidity and mortality, but its etiology and risk factors are poorly understood. We undertook a scoping review to illustrate the breadth of risk factors for preterm birth that have been reported in the literature. We conducted a search in the PubMed database for articles published in the previous 5 years. We determined eligibility for this scoping review by screening titles and abstracts, followed by full-text review. We extracted odds ratios and other measures of association for each identified risk factor in the articles. A total of 2,509 unique articles were identified from the search, of which 314 were eligible for inclusion in our final analyses. We summarized risk factors and their relative impacts in the following categories: Activity, Psychological, Medical History, Toxicology, Genetics, and Vaginal Microbiome. Many risk factors for preterm birth have been reported. It is challenging to synthesize findings given the multitude of isolated risk factors that have been studied, inconsistent definitions of risk factors and outcomes, and use of different covariates in analyses. Novel methods of analyzing large datasets may promote a more comprehensive understanding of the etiology of preterm birth and ability to predict the outcome.

Key Points

  • Preterm birth is difficult to predict.

  • Preterm birth has many diverse risk factors.

  • Holistic approaches may yield new insights.

Publication History

Received: 06 March 2023

Accepted: 22 August 2023

Article published online:
25 September 2023

© 2023. Thieme. All rights reserved.

Thieme Medical Publishers, Inc.
333 Seventh Avenue, 18th Floor, New York, NY 10001, USA

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