Perinatal mood and anxiety disorders and adverse perinatal outcomes: a retrospective cohort study

Perinatal mood and anxiety disorders (PMADs) are common mental health complications of pregnancy, affecting approximately 1 in 5 women in the US. Serious mental illness (SMI) is less common and clinically distinct. We examined associations between the number of documented PMAD conditions and, separately, SMI with adverse perinatal outcomes, and whether associations varied by race/ethnicity and chronic hypertension. This retrospective cohort study included 46,729 singleton births delivered at a tertiary obstetric hospital in South–Central Louisiana from 2017 to 2022. PMAD included anxiety, depression, panic disorder, and obsessive–compulsive disorder, while SMI included bipolar disorder, schizophrenia, and postpartum psychosis. Conditions were identified from medical records and modeled as distinct exposure groups. PMAD burden was categorized as 0, 1, 2, or ≥ 3 documented conditions, while SMI was modeled as any versus none. Outcomes included preterm birth (PTB), low birthweight (LBW), cesarean delivery, hypertensive disorders of pregnancy (HDP), gestational diabetes, delivery complications, postpartum hemorrhage, and postpartum readmission. Modified Poisson regression estimated adjusted risk ratios (aRRs) and 95% confidence intervals (CIs), accounting for maternal characteristics and repeated deliveries. Of 46,729 births, 70.6% had no documented PMAD or SMI, 26.9% had PMAD only, 0.4% had SMI only, and 2.2% had both. Risk generally increased with the number of documented PMAD conditions. Women with ≥ 3 PMAD conditions had increased risk of PTB (aRR = 1.54, 95% CI = 1.32–1.79), LBW (aRR = 1.33, 95% CI = 1.09–1.62), cesarean delivery (aRR = 1.11, 95% CI = 1.01–1.22), HDP (aRR = 1.16, 95% CI = 1.01–1.33), and delivery complications (aRR = 1.43, 95% CI = 1.14–1.79). After adjustment for PMAD burden, SMI was associated with LBW, while associations with other outcomes were less precise. Anxiety was associated with increased risk across all eight outcomes, although depression and bipolar disorder showed larger point estimates for selected outcomes. Associations varied by race/ethnicity for six outcomes and by chronic hypertension for four. Greater documented PMAD burden was generally associated with higher risk of several adverse perinatal outcomes after accounting for SMI. Associations also differed across individual mental health conditions and maternal risk groups. These findings highlight heterogeneity in perinatal mental health risks and support distinguishing specific conditions rather than treating diagnosis counts as clinical severity. Not applicable.