Changing risk factors for postpartum depression in mothers admitted to a perinatal center

Background: The Edinburgh postnatal depression scale (EPDS) is commonly used in screening for major postpartum depression (PPD). We explored the clinical factors associated with score changes. Methods: Mothers (n=1,287) who delivered a single live-born infant in Kokura Medical Center in Japan during 2018–2019 were analyzed. The EPDS-Japanese version was conducted at the first and fourth weeks after childbirth. Scores of ≥9 were considered to indicate an increased risk of PPD. Results: The scores improved during the four-week period (5.03±0.12 to 3.79±0.10). Primiparity, Cesarean section (CS), and a low Apgar score were identified as initial risk factors, however, primiparity remained in the multivariate analysis (aOR 2.02, 95% CI 1.37–2.97). Age ≥35 years was associated with worsened scores (aOR 1.88, 95%CI 1.01–3.51), but CS improved (aOR 0.38, 95%CI 0.21–0.70). Primiparity, CS, and neonatal respiratory support were the initial risk factors, while infant anomaly was a late risk factor in mothers whose infants were admitted to the neonatal intensive care unit (NICU) (aOR 3.35, 95%CI 1.31–8.56). In mothers of infants with an NICU stay of ≥4 weeks, infant anomaly was associated with worsened scores (aOR 6.61, 95%CI 1.11–39.3), while respiratory support was associated with improved scores (aOR 0.09, 95%CI 0.01–0.65). Twenty-six mothrs with worsened scores received psychiatric support; three developed PPD. Two of the three were ≥35 years of age, neither of their infants had anomalies. Conclusion: Maternal aging and infant anomaly were risk factors for PPD. PPD occurred in mothers with worsened EPDS scores after mental care. Puerperants with worsening risk factors should be targeted to control PPD.