Racial/Ethnic Differences in Correlates of Spontaneous and Medically-Indicated Late Preterm Births among Adolescents

Study Objective To investigate the racial/ethnic differences in the correlates of spontaneous and medically-indicated late preterm birth (LPTB), defined as deliveries between 34 0/7 and 36 6/7 weeks gestation, among US adolescents. Design Population-based, retrospective cohort study. Setting Births in the United States to adolescents in 2012. Participants Adolescents (younger than 20 years; n = 171,573) who delivered nonanomalous singleton first births between 34 and 44 weeks of gestation. Interventions and Main Outcome Measures Bivariate and multivariable logistic regression were used to evaluate the associations between maternal risk factors and spontaneous and medically-indicated LPTB, stratified according to maternal race/ethnicity. Results Risk factors for spontaneous LPTB included single marital status among Asian adolescents; no insurance coverage among whites, Asian, and Hispanic adolescents; inadequate prenatal care among all racial/ethnic groups except American Indian, and adequate plus prenatal care among all races/ethnicities; prenatal smoking among whites and black adolescents; insufficient gestational weight gain among all racial/ethnic groups except American Indian; and prepregnancy underweight among white, black, and Hispanic adolescents. Risk factors for medically-indicated LPTB included inadequate prenatal care among white, black, and Hispanic adolescents, and adequate plus prenatal care among all racial/ethnic groups except Asian; insufficient gestational weight gain among white, black, and Hispanic adolescents; and prepregnancy overweight and obesity among white, black, and Hispanic adolescents. Conclusion Our results show racial/ethnic differences in the correlates of spontaneous and medically-indicated LPTB among US adolescents and support the need for risk-specific interventions among different racial/ethnic groups.