Trends, characteristics, and outcomes of pregnancy in women with attention-deficit hyperactivity disorder: A nationwide analysis.

Objective: To assess clinical and obstetric characteristics associated with pregnant patients with a diagnosis of attention-deficit hyperactivity disorder (ADHD).

Methods: This serial cross-sectional study queried the Agency of Healthcare Research and Quality's Healthcare Cost and Utilization Project National Inpatient Sample. The study population was 16,759,786 hospital deliveries from 2016 to 2020. Patients with a diagnosis of another mental health condition (anxiety disorder, depressive disorder, bipolar disorder, and schizophrenia disorder) were excluded. A multivariable binary logistic regression model was created to assess clinical and obstetric characteristics associated with ADHD. A 1-to-1 propensity score matching was performed to assess severe maternal morbidity.

Results: A total of 33,415 patients with ADHD were identified (prevalence rate: 19.9 per 10,000 deliveries, 95% confidence interval [CI] 19.8-20.2). During the study period, the prevalence of pregnant patients with a diagnosis of ADHD increased 39.4 % from 16.5 to 23.0 per 10,000 (P-trend<0.001). Younger patients were more likely to have the diagnosis of ADHD (P<0.001), including one in 373 patients aged <25 years and one in 227 patients in aged <20 years. In a multivariable analysis, age <25 years (adjusted-prevalence rate ratio [aRR] 2.80, 95%CI 2.57-3.04), White race (adjusted-RR 2.13, 95%CI 1.83-2.47), asthma (adjusted-RR 3.68, 95%CI 3.58-3.79), tobacco use disorder (adjusted-RR 2.04, 95%CI 1.97-2.12), alcohol use disorder (adjusted-RR 2.48, 95%CI 2.13-2.89), and illicit drug use disorder (adjusted-RR 2.19, 95%CI 2.09-2.29) were associated with ADHD. A classification-tree identified that White, asthmatic patients aged ≤21 years had the highest ADHD prevalence rate (209 per 10,000 or one in 48 patients). Rates of early-term, late-preterm, and early-preterm, peri-viable deliveries and cesarean delivery were only modestly increased. In a propensity score matched model, the measured severe maternal morbidity was overall similar between the ADHD and non-ADHD groups (19.5 versus 18.1 per 1,000 deliveries, incidence rate ratio 1.08, 95 %CI 0.96-1.20).

Conclusion: This nationwide assessment suggests the prevalence of ADHD in pregnancy is gradually increasing in the United States. Observed associations with younger age, asthma, and substance use could possibly provide useful insights in perinatal care for screening, support, and treatment.