Perinatal mental health refers to mental health issues that can arise during pregnancy and in the postpartum period. Despite their prevalence, significant service disparities exist in perinatal mental health care provision. This chapter explores the extent of the service gaps and the need for anti-oppressive practice in perinatal mental health services. Literature on perinatal mental health and service concerns is considered, including the prevalence of mental health issues among pregnant and postpartum women, the impact of these challenges on mothers and their children, the barriers to accessing treatments, and the role of power and privilege. The chapter also examines potential anti-oppressive practices for closing the service gap in perinatal mental health care: adopting culturally responsive and trauma-informed treatment, integrating perinatal mental health care into primary care, increasing wrap-around services, offering telehealth services, addressing implicit bias and stereotypes, and incorporating social determinants of health.