Depression, and to a lesser extent postpartum depressive symptoms, have been associated with characteristics of the social environment and social capital. Up to the present, mostly cross-sectional studies have explored such an association without providing a clear temporal relationship between social capital and depression.

To estimate prospectively the effect of individual-level self-reported maternal social capital during pregnancy on postpartum depressive symptoms.

Prospective mother–child cohort (Rhea study).

4 prenatal clinics in Heraklion, Crete, Greece.

All women for one year beginning in February 2007. From the 1388 participants, complete data were available for 356 women.

Women self-completed two questionnaires: The Social Capital Questionnaire at about the 24th week of gestation and the Edinburgh Postnatal Depression Scale (range 0–30) at about the 8–10th week postpartum. Maternal social capital scores were categorized into three groups: the upper 10% was the high social capital group, the middle 80% was the medium and the lowest 10% was the low social capital group that served as the reference category. Multivariable log-binomial and linear regression models were performed for: the whole available sample; for participants with a history of depression and/or prenatal EPDS≥13; for participants without any previous or current depression and prenatal EPDS score<13. Potential confounders included demographic, socio-economic, lifestyle and pregnancy characteristics that have an established or potential association with maternal social capital in pregnancy or postpartum depressive symptoms or both.

Higher maternal social capital was associated with lower EPDS scores (highest vs lowest group: β-coefficient=−3.95, 95% CI −7.75, −0.14). Similar effects were noted for the subscale value of life/social agency (highest vs lowest group: β-coefficient=−5.96, 95% CI −9.52, −2.37). This association remained significant for women with and without past and/or present depression only for the subscale value of life/social agency although with a more imprecise estimate. No effect was found for participation, a structural dimension of social capital.

Women with higher individual-level social capital in mid-pregnancy reported less depressive symptoms 6–8 weeks postpartum. Given the proposed association of perceptions of the social environment with postpartum depressive symptoms, health professionals should consider evidence-based interventions to address depression in a social framework.