The association between a pregnant mother’s vitamin D status and depressive symptoms has yielded inconsistent results. It is possible that other factors play a role in this association, as depression can have multiple causes. Recognizing the significance of the husband’s participation in antenatal care, this study aimed to examine whether the husband’s involvement moderates the link between the mother’s vitamin D status and depressive symptoms during pregnancy.

A total of 2983 Chinese married pregnant women, in their 25–35 weeks of pregnancy, completed questionnaires to assess their levels of depressive symptoms and the involvement of their husbands in their antenatal care appointments. Additionally, their serum levels of vitamin D were measured.

After adjusting for maternal age, parity, and socio-economic status, the husband’s involvement in antenatal care moderated the association between maternal vitamin D status and depressive symptoms during pregnancy (β = 2.03, p = 0.035). Specifically, when their husbands were not regularly present for antenatal care appointments, mothers with suboptimal vitamin D levels experienced more depressive symptoms than those with optimal levels. However, there were no noticeable differences in depressive symptoms between vitamin D groups for mothers whose husbands attended all antenatal care appointments.

Pregnant women who have suboptimal vitamin D levels and lack support from their spouses are most vulnerable to experiencing depression. It is crucial to holistically assess the social and physiological needs of expectant mothers to reduce their risk of antenatal depression.