["Journal of Marital and Family Therapy, Volume 52, Issue 3, July 2026. ", "\nABSTRACT\nThe transition to parenthood is a period of heightened vulnerability for many couples, often marked by increased conflict. Attachment insecurity is a known risk factor, linked to dysfunctional conflict dynamics in couples more broadly. Yet, the emotional processes driving these patterns remain underexplored, especially from a dyadic perspective. This study examined emotional flooding—a form of dyadic emotion dysregulation—as a potential intermediary variable linking attachment to conflict behaviors. Ninety‐six mixed‐sex couples completed questionnaires on attachment and emotional flooding before engaging in observationally coded conflict discussions during the third trimester of pregnancy. Actor partner interdependence models extended to mediation (APIMeM) revealed that men's attachment anxiety was positively associated with observed conflict withdrawal indirectly through their own emotional flooding. Women's attachment anxiety was positively associated with observed conflict hostility through their own emotional flooding. Findings highlight emotional flooding as a pathway through which attachment shapes mixed‐sex couples' vulnerability to gendered conflict patterns.\n"]