Background <p>Intimate partner violence is a serious social problem affecting maternal mental health and has been confirmed to be associated with postpartum depression. However, the mechanisms through which intimate partner violence influences postpartum depression remain unclear, particularly the mediating role of fear of birth and the buffering effect of antenatal care, which require further investigation.</p> Methods <p>This research adopted a cross-sectional design and surveyed 562 postpartum women from a tertiary hospital in Hubei Province, China. Data were analyzed to examine the effects of intimate partner violence on postpartum depression, the mediating role of fear of birth, and the moderating effect of antenatal care attendance.</p> Results <p>The results showed that intimate partner violence significantly predicted postpartum depression, and fear of birth partially mediated this relationship. Additionally, antenatal care significantly moderated the association between fear of birth and postpartum depression. Among those who attended antenatal care, the impact of fear of birth on postpartum depression was weaker, whereas this effect was more pronounced among women who did not attending at antenatal care.</p> Conclusions <p>This study shed light on the mechanisms through which intimate partner violence influences postpartum depression, with a particular emphasis on the mediating role of fear of birth and the moderating role of antenatal care in alleviating maternal psychological stress. These findings provide novel theoretical grounding for clinical interventions targeting maternal mental health. The results suggest that healthcare providers should strengthen screening for intimate partner violence, deliver targeted psychological interventions for women experiencing fear of birth, and enhance the accessibility and quality of antenatal care services to reduce the risk of postpartum depression.</p>