Epidemiologic Features of Preterm Birth Among Infants With Trisomy 21 in Texas, 1999-2018.

The rate of preterm birth among infants with trisomy 21 (22%) is around twice that among the general population (10%). We conducted a descriptive epidemiologic study to address the gap in knowledge on what maternal and infant factors are associated with preterm birth among infants with trisomy 21. Singleton infants with trisomy 21 born between 1999 and 2018 were identified from the Texas Birth Defects Registry. We used multivariable logistic regression to assess associations between preterm birth and 14 maternal and infant characteristics. Statistically significant associations were observed between preterm birth and maternal race/ethnicity, maternal age, maternal birthplace, prenatal care, smoking, infant sex, and infant delivery year. For instance, preterm birth was associated with maternal age (adjusted odds ratio [aOR] 1.44, 95% CI: 1.23-1.70 for ≥ 40 vs. 25-29 years) and prenatal care (aOR 1.59, 95% CI: 1.25-2.03 for no care versus any care). Our findings contribute toward a better understanding of the risk profile of preterm birth among infants with trisomy 21 and can guide further research on risk factors and potential interventions for reducing preterm birth rates in this population.