Cross-Generational Contributors to Preterm Birth in California: Singletons Based on Race/Ethnicity

Am J Perinatol. 2019 Mar;36(4):383-392. doi: 10.1055/s-0038-1668554. Epub 2018 Aug 19.


Objective: Multiple studies have examined cross-generational patterns of preterm birth (PTB), yet results have been inconsistent and generally focused on primarily white populations. We examine the cross-generational PTB risk across racial/ethnic groups.

Study design: Retrospective study of 388,474 grandmother-mother-infant triads with infants drawn from birth registry of singleton live births between 2005 and 2011 in California. Using logistic regression (odds ratios [ORs] and confidence intervals [CIs]), we examined the risk of preterm delivery by gestational age, sociodemographic, socioeconomic, and obstetric clinical characteristics stratified by maternal race/ethnicity.

Results: The risk of having a preterm infant <32 weeks was greater for women born at <32 weeks (OR: 2.09, 95% CI: 1.62-2.70) and 32 to 36 weeks (OR: 1.51, 95% CI: 1.35-1.70). This increased risk of preterm delivery was present among women in all race/ethnicity groups (white [AOR: 2.00, 95% CI: 1.52-2.63), black [AOR: 1.79, 95% CI: 1.37-2.34], Hispanic [AOR: 2.39, 95% CI: 2.05-2.79], and Asian [AOR: 2.12, 95% CI: 1.20-3.91]), with hypertension as the only consistent risk factor associated with increased risk of preterm delivery.

Conclusion: Our findings suggest a cross-generational risk of PTB that is consistent across race/ethnicity with hypertension as the only consistent risk factor.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • California
  • Female
  • Genetic Predisposition to Disease
  • Humans
  • Hypertension / genetics
  • Hypertension, Pregnancy-Induced* / genetics
  • Logistic Models
  • Maternal Age
  • Parity
  • Pregnancy
  • Premature Birth / ethnology
  • Premature Birth / genetics*
  • Retrospective Studies
  • Risk Factors
  • Socioeconomic Factors