Poster Session 2
Category: Health Equity/Community Health
Poster Session 2
Hiba J. Mustafa, MD (she/her/hers)
Director of Fetal Surgery, Director of Placenta Accreta Spectrum Program
Indiana University School of Medicine, Riley Children's Hospital
Indianapolis, Indiana, United States
Jana Karam, MD
Lebanese American University School of Medicine
Beirut, Beyrouth, Lebanon
William A. Grobman, MBA, MD
Professor
Warren Alpert Medical School of Brown University
Providence, Rhode Island, United States
Kevin Moss
Indiana University
Indianapolis, Indiana, United States
Jasmine Johnson, MD
Indiana University Health
Indianapolis, Indiana, United States
.jpg "Maged M. Costantine, MD (he/him/his) photo")
Maged M. Costantine, MD (he/him/his)
Director MFM
Ohio State University
Columbus, Ohio, United States
.jpg "Heather A. Frey, MD, MSCI (she/her/hers) photo")
Heather A. Frey, MD, MSCI (she/her/hers)
Associate Professor
The Ohio State University Wexner Medical Center
The Ohio State University Wexner Medical Center, Ohio, United States
Moti Gulersen, MD, MSc
Assistant Professor
Thomas Jefferson University
PHILADELPHIA, Pennsylvania, United States
Vincenzo Berghella, MD (he/him/his)
Professor, Director
Thomas Jefferson University
Philadelphia, Pennsylvania, United States
.jpg "Alireza A. Shamshirsaz, MD (he/him/his) photo")
Alireza A. Shamshirsaz, MD (he/him/his)
Department Director, Professor of Surgery
Boston Children's Hospital, Harvard Medical School
Boston, Massachusetts, United States
To assess whether maternal nativity (US-born vs. non–US-born) is associated with preterm birth (PTB) risk among nulliparous individuals with twin pregnancies and if this association varies by race/ethnicity.
Study Design:
We conducted a cross-sectional analysis of the US National Center for Health Statistics natality dataset (2016–2023), including nulliparous individuals aged 15–44 who delivered live-born twins. Singleton, higher-order multiples, and those with missing key data were excluded. Maternal nativity (US-born vs. non–US-born) was analyzed overall and stratified by race/ethnicity. Covariates included age, education, insurance, prenatal care, smoking, pre-pregnancy BMI, diabetes, hypertension, and year. PTB was defined as < 37 weeks, further categorized as extremely preterm (< 29 weeks), moderately preterm (29–33 weeks), and late preterm (34–36 weeks). Binary and multinomial logistic regression models were used to estimate adjusted odds ratios (aOR) with 95% confidence intervals (CIs).
Results:
Among 467,446 twin pregnancies, 39.5% delivered at term (≥37 weeks), while 60.5% were preterm. Of PTBs, 41.1% were late preterm, 14.6% moderately preterm, and 4.8% extremely preterm. Non–US-born individuals had lower odds of PTB than US-born peers (aOR 0.89, 95% CI 0.88–0.91). The greatest reduction in PTB risk was observed among non–US-born Black individuals (aOR 0.65, 95% CI 0.62–0.68). Non–US-born status was associated with lower odds of extremely preterm (aOR 0.88, 95% CI 0.84–0.91), moderately preterm (aOR 0.85, 95% CI 0.83–0.87), and late preterm birth (aOR 0.91, 95% CI 0.89–0.93).
Conclusion:
In this national cohort, non–US-born individuals had consistently lower PTB risk than US-born counterparts with twin pregnancies across racial and ethnic groups. These findings highlight nativity as an important social determinant of preterm birth among twins. Future research should elucidate mechanisms underlying these differences and consider broader social and structural factors influencing PTB in multiples.