Development and validation of the Peripartum depression scale

•Peripartum Depression Scale (PDS) is a new measure for pregnancy and postpartum.•PDS covers diagnostic criteria from DSM-5-TR for major depressive disorder.•In addition, PDS includes peripartum depression-specific symptoms.•High reliability and validity of the new scale was demonstrated.•Analyses ensured validity in both pregnant and postpartum women subsamples. Peripartum depression (PPD) is the most common peripartum mental health problem. However, none of the available questionnaires evaluates depressive symptoms according to the latest DSM-5-TR (APA, 2022). Peripartum Depression Scale (PDS) is a new measure of PPD developed according to DSM-5-TR full criteria and postpartum-specific symptoms described in the literature. The aim of this study was to validate a new scale to assess depression in pregnancy and postpartum. In this online cross-sectional study, 513 pregnant women and 751 women within the 12 months postpartum completed a new PDS consisting of 43 items from Criterion A, rated on a four-point scale, and seven items on the remaining DSM-5-TR criteria. They also completed Edinburgh Postnatal Depression Scale (EPDS), Depression, Anxiety and Stress Scale (DASS), and General Data Questionnaire. Confirmatory factor analysis confirmed that the one-factor model had a poor fit, but the 9-factor with a second-order factor in postpartum sample and 10-factor model with a second-order factor in pregnant sample, on the same 42-item version of scale, had a good fit to the data. The reliability of McDonald's ω of .96 was very high in both pregnant and postpartum women. Convergent and known-groups validity was demonstrated; however, correlations with stress were high. Clinical interview was not administered. Peripartum Depression Scale is a 42-item instrument which is shown to be a valid and reliable measure to assess depression symptoms both during pregnancy and the full postpartum year according to DSM-5-TR criteria and current literature on peripartum-specific symptoms.