OBJECTIVES: To estimate the prevalence of postpartum depression (PPD) within one year after birth and compare demographics, clinical characteristics, and healthcare costs between mothers with and without PPD.

METHODS: Adult females were identified in the Merative™ MarketScan® Commercial Database with >1 inpatient admission for a live birth (2019-2021), enrollment for 12 months pre-admission (baseline) and post-discharge (follow-up), without baseline major depressive disorder (MDD). Follow-up PPD was identified by a non-diagnostic claim with a PPD diagnosis. Demographics were assessed on the live birth date. Comorbidities and costs were assessed during baseline and follow-up and compared between groups using t-tests and chi-square tests. Difference-in-difference analysis estimated follow-up costs attributable to PPD.

RESULTS: A total of 180,279 mothers qualified; 7,698 (4.3%) with PPD and 172,581 (95.7%) without PPD. Mothers with PPD had a greater baseline Charlson Comorbidity Index (0.14 +0.44 vs. 0.10 +0.37, p<0.001) and nearly twice the prevalence of anxiety disorders (13.6% vs. 7.5%) and severe stress reactions/adjustment disorders (6.5% vs. 3.3%; both p<0.001). Twenty-four percent of mothers with PPD had a follow-up MDD diagnosis, compared to 4.1% of mothers without PPD (p<0.001). Mothers with PPD had $1,722 greater baseline costs than mothers without PPD ($9,461 vs. $7,739; p<0.001), and $3,147 greater costs during follow-up ($7,570 vs. $4,423; p<0.001). Total costs decreased 42.8% between baseline and follow-up among mothers without PPD, compared to a 20.0% decrease among mothers with PPD. Difference-in-difference analysis estimated $1,425 (18.8%) of follow-up costs among mothers with PPD to be attributable to the PPD diagnosis.

CONCLUSIONS: Mothers with PPD have baseline mental health diagnoses and other comorbidities that may predispose them to depression after giving birth. These pre-natal comorbidities appear to persist in the post-natal period and likely contribute to higher healthcare costs both pre- and post-delivery. These observations highlight the need for mental health screening and care throughout the perinatal period.