Perinatal substance use disorder: Examining the impact on adverse pregnancy outcomes

Substance use disorder is a growing concern in the USA, especially among pregnant women. This study was undertaken to assess the impact of substance use disorder on adverse pregnancy outcomes using a nationwide sample of inpatient pregnancy hospitalizations in the USA, and to elucidate the influence on each type of adverse pregnancy outcome. A cross-sectional analysis of inpatient pregnancy hospitalizations in the USA from the Healthcare Cost and Utilization Project National Inpatient Sample from 2016 to 2020 was conducted. International Classification of Diseases – 10th revision and diagnosis-related group codes were used to identify inpatient pregnancy-related delivery hospitalizations with a substance use disorder and/or adverse pregnancy outcomes. Propensity score matching and multiple logistic regression analyses were undertaken to predict the likelihood of adverse pregnancy outcomes among pregnancy hospitalizations with and without substance use disorder. Subgroup analyses were performed to estimate the impact of substance use disorder on each adverse pregnancy outcome. From 3,238,558 hospitalizations, the prevalence of adverse pregnancy outcomes was substantially higher among pregnancy hospitalizations with substance use disorder (35.6%) compared with pregnancy hospitalizations without substance use disorder (25.1%, p<0.001). After matching and model adjustment for sociodemographic covariates, substance use disorder was identified as an independent predictor of adverse pregnancy outcomes adjusted odds ratio (aOR) 1.47, 95% confidence interval (CI) 1.45–1.49. In subgroup analyses based on type of adverse pregnancy outcome, the greatest exposure risks were fetal growth restriction (aOR 1.96, 95% CI 1.91–2.01), antepartum haemorrhage (aOR 1.79, 95% CI 1.73–1.85) and preterm birth (aOR 1.65, 95% CI 1.62–1.68). Patients with substance use disorder are at higher risk of adverse pregnancy outcomes, particularly fetal growth restriction, antepartum haemorrhage and preterm birth.