Perinatal (antenatal and postnatal) depression is increasingly a target of improved awareness, clinical research and public health efforts, yet it remains a serious health concern for both pregnant and postpartum women. It has far-reaching consequences, affecting not only the women but also their children and relationships. In addition, mothers with depressive symptoms have been found to have more complex behavioural interactions with their children, to be less responsive and sensitive, and to be more intrusive in their interactions. This book discusses the role of social support during pregnancy.