RecruitingPhase 3Drug trialBrexanolone Lifting Outcomes Of MomsThe purpose of this research study is to test the study drug, LPCN 1154A, as a possible treatment for postpartum depression (PPD). The trial aims to determine: * If LPCN 1154A reduces depressive symptoms in subjects with severe PPD * How well LPCN 1154A is tolerated and what side effects it may cause