Identifying postpartum depression: Using key risk factors for early detection

Background Personal and family history of psychiatric disorders are key risk factors for postpartum depression (PPD), yet their combined contribution has been understudied. Objective To examine personal and family psychiatric history, alone and combined, and their effect on absolute risk and relative risk (RR) of mild/moderate or severe PPD. Methods In this cohort study, we used data from 142 064 childbirths with PPD screenings from 2015 to 2021 merged with population registers. Exposures were personal and family psychiatric history defined as a psychiatric hospital contact or psychotropic prescription fills by index mothers and their parents prior to delivery. Outcomes were mild/moderate PPD (Edinburgh Postnatal Depression Scale, cut-off: ≥11 within 12 weeks post partum) and severe PPD (antidepressant fill or depression diagnosis within 6 months post partum). We calculated absolute risks and RRs using Poisson regression models adjusted for parity, education, maternal age, and calendar year. Findings Of the 142 064 participants, 23.4% had no psychiatric history, 47.4% had only family history, 6.0% had only personal history, and 23.2% had both. The latter group had the highest risk of PPD: absolute risk of mild/moderate PPD was 11.7% (95% CI 11.5%; 11.8%), and adjusted RR: 2.35 (95% CI 2.22; 2.49). Alone, personal psychiatric history was the most potent risk factor. Dose–response relationship based on severity of personal and family psychiatric history was found. Discussion Our study documents a substantial association between personal and family psychiatric history and PPD risk. Clinical implications Evaluating combinations of risk factors is important to improve risk assessment.