Abstract
OBJECTIVE: Although maternal psychopathology has long been suggested to increase the risk of neurodevelopmental disorders, whether or not postpartum depression (PPD), a condition diagnosed after delivery, is associated with increased risk of diagnosis of autism spectrum disorders (ASDs) in the offspring, is unclear. Therefore, we tested the hypothesis that PPD diagnosis in the mother would increase the risk of ASD diagnosis in her offspring, and that the association would be independent of gestational age at birth, child's sex, or race/ethnicity. METHOD: We conducted a retrospective cohort study among children born between 2010 and 2021 by examination of individual patient maternal-child linked electronic health records (EHRs) (N = 297,720) from Kaiser Permanente Southern California hospitals. International Classification of Diseases codes listed in the EHR were used to identify diagnosed PPD and ASD cases. Marginal Cox proportional hazard models were fit to evaluate the potential association between maternal PPD diagnosis and the diagnosis of ASD in the offspring. Results are reported as incidence rates and adjusted hazard ratios (HRs) with 95% CIs. RESULTS: Children of mothers diagnosed with PPD had higher rates of ASD diagnosis than children of mothers without the diagnosis of PPD (9.11 vs 5.48 per 1000 person-years, HR =1.57, CI = 1.49, 1.65). PPD diagnosis in mothers was associated with ASD diagnosis in the offspring for both preterm and term-born children, boys as well as girls, and no strong racial/ethnic heterogeneity in the association was detected. CONCLUSION: Postpartum depression in the mother is associated with an increased risk of ASD diagnosis in her child, independent of gestational age at birth, child sex, and race/ethnicity.