Fatherhood has a direct and substantial impact on men’s physical, mental and social health, and sense of paternal generativity over their life course. This chapter, the second of a pair in this volume, explores the bidirectional impact of fatherhood on men’s health in the perinatal period. It pulls together a scattered fatherhood literature and articulates six broad pathways by which fatherhood could potentially impact on men’s health and development, both positively and negatively. This systematic exploration represents a new focus for the Maternal and Child Health (MCH) field, especially in addressing the perinatal time period, a time not usually thought of as impacting on men’s health. This chapter attempts to establish a firmer scientific knowledge base and rationale to support new, targeted perinatal fatherhood health programs, policies, and research. Hopefully, these will also further contribute to the growing efforts to expand men’s and women’s parental gender role expectations and equity, and enhance the parenting health and men’s health movements. Similar to the dual orientation of the women’s preconception health initiatives, earlier, healthier, and more actively engaged fatherhood should lead to both improved reproductive and infant health outcomes and men’s own improved health across the life course.