Am J Perinatol
DOI: 10.1055/s-0043-1776345
Original Article

Impact of Race/Ethnicity and Insurance Status on Obstetric Outcomes: Secondary Analysis of the NuMoM2b Study

Maria S. Rayas
1   Department of Pediatrics, University of Texas Health Science Center San Antonio, San Antonio, Texas
Jessian L. Munoz
2   Department of Obstetrics and Gynecology, University of Texas Health Science Center San Antonio, San Antonio, Texas
2   Department of Obstetrics and Gynecology, University of Texas Health Science Center San Antonio, San Antonio, Texas
Jennifer Kim
1   Department of Pediatrics, University of Texas Health Science Center San Antonio, San Antonio, Texas
Cheyenne Mangold
1   Department of Pediatrics, University of Texas Health Science Center San Antonio, San Antonio, Texas
Alvaro Moreira
1   Department of Pediatrics, University of Texas Health Science Center San Antonio, San Antonio, Texas
› Author Affiliations
Funding This work was supported by Parker B. Francis (A.M.); Eunice Kennedy Shriver National Institute Of Child Health & Human Development of the National Institutes of Health K23HD101701 (A.M.), National Center for Advancing Translational Sciences, National Institute of Health Grant KL2 TR002646 (M.S.R.), and the Cystic Fibrosis Foundation (M.S.R.).


Objective This study aimed to investigate the impact of race/ethnicity and insurance status on obstetric outcomes in nulliparous women.

Study Design Secondary analysis of the Nulliparous Pregnancy Outcomes Study Monitoring Mothers-To-Be. Obstetric outcomes included the development of a hypertensive event during pregnancy, need for a cesarean section, delivery of a preterm neonate, and postpartum hemorrhage.

Results Of 7,887 nulliparous women, 64.7% were non-Hispanic White (White), 13.4% non-Hispanic Black (Black), 17.8% Hispanic, and 4.1% were Asian. Black women had the highest rates of developing new-onset hypertension (32%) and delivering preterm (11%). Cesarean deliveries were the highest in Asian (32%) and Black women (32%). Individuals with government insurance were more likely to deliver preterm (11%) and/or experience hemorrhage after delivery. In multivariable analyses, race/ethnicity was associated with hypertension and cesarean delivery. More important, the adjusted odds ratios for preventable risk factors, such as obesity, diabetes, and severe anemia were greater than the adjusted odds ratios for race/ethnicity in terms of poor maternal outcome.

Conclusion Although disparities were observed between race/ethnicity and obstetric outcomes, other modifiable risk factors played a larger role in clinical differences.

Key Points

  • Race or insurance alone had mixed associations with maternal morbidities.

  • Race and insurance had low associations with maternal morbidities.

  • Other, modifiable risk factors may be more important.

  • Both social and biological factors impact health disparities.

Authors' Contributions

M.S.R.: manuscript writing, interpretation of findings; J.L.M.: study design, review of manuscript; A.B.: study design, review of manuscript; C.M.: data analytics, review of manuscript; J.K.: manuscript writing; A.M.: study design, data analytics, manuscript writing, oversight.

Data Availability Statement

Data are publicly accessible to researchers upon request via the National Institutes of Health Data and Specimen Hub Web site: The corresponding author (A.M.) should be contacted if someone has questions regarding the study or if they want some assistance on how to request data from the National Institutes of Health Data and Specimen Hub.

Publication History

Received: 14 December 2022

Accepted: 26 September 2023

Article published online:
07 November 2023

© 2023. Thieme. All rights reserved.

Thieme Medical Publishers, Inc.
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