Research on postpartum onset obsessive-compulsive disorder (OCD) has focused exclusively on females. However, the authors present four cases of males with OCD onset that coincide with a spouse's pregnancy or delivery. The rapid onset and content of obsessions and compulsions are remarkably similar to those reported in previous studies of postpartum OCD in females. Each patient also responded to cognitive-behavioral therapy using exposure procedures. The implications of these cases for etiological models of postpartum OCD and future research directions are discussed.