Perinatal depressive symptoms and child temperament at two years: The moderating role of child sleep duration.

Background: Perinatal depression has been linked to higher negative affectivity (NA) in children, though the strength of this association is variable. Infant sleep, a known protective factor, may moderate this relationship though this has not been tested.

Objective: To examine whether within-person changes in depressive symptoms across pregnancy and postpartum were linked to child NA, and whether infant sleep duration moderated these effects.

Methods: This study analyzed secondary data from 3906 postpartum individuals recruited during the COVID-19 pandemic (2020-2021). Online surveys were administered at enrollment (<35 weeks' gestation), 6-, 12-, and 24 months postpartum, capturing demographic information, depressive symptoms, child NA (24 months), delivery outcomes, and infant sleep duration (12 months). A generalized linear model (GLM) tested the effects of within-person changes in perinatal depressive symptoms and chronic depressive symptom levels on child NA. The moderating role of infant sleep duration was also assessed.

Results: Reductions in depressive symptoms from pregnancy to postpartum were associated with lower child NA, but only at sufficient infant sleep duration (B = -0.01, p = .040, f = 0.002). Chronic perinatal depressive symptoms were associated with greater child NA (B = 0.03, p < .001, f = 0.06); this risk was attenuated at longer infant sleep duration.

Conclusion: Child NA was shaped by both chronic levels and within-person patterns of depressive symptoms. Infant sleep duration buffered risk of chronic depressive symptoms, and amplified the protective effects of patterns of symptom reduction, underscoring infant sleep duration as a key intervention target.