ABSTRACT Peripartum cardiomyopathy (PPCM) is a complication of pregnancy occurring in 1 in 2000 live births, which remains a major cause of maternal morbidity and mortality. Inhibition of prolactin with the dopaminergic agonist bromocriptine appears to improve outcomes in small clinical studies of PPCM in Africa and Europe; however, no randomized trial has been performed in a diverse multi-racial North American cohort comparing bromocriptine against standard heart failure therapy. This multicenter trial, Randomized Evaluation of Bromocriptine In Myocardial Recovery Therapy for Peripartum Cardiomyopathy (REBIRTH), will evaluate whether the addition of bromocriptine to standard therapy improves outcomes for women with PPCM. This trial will randomize 200 women with PPCM to eight weeks of bromocriptine or placebo. Left ventricular ejection fraction will be determined by echocardiography at study entry, and reassessed at 6 and 12 months after randomization to determine whether the addition of bromocriptine improves left ventricular function and overall clinical outcomes. For women presenting with PPCM, echocardiographic assessment of left ventricular dysfunction and remodeling helps predict the probability of recovery. This proposal will evaluate whether global longitudinal strain or left ventricular diastolic volume will predict the therapeutic response to bromocriptine. The therapeutic impact of bromocriptine is theoretically a result of the reduction of prolactin and prolactin fragments collectively known as vasoinhibins. This investigation will investigate whether higher levels of these biomarkers predict greater benefit from bromocriptine. Breastfeeding raises prolactin levels, and the impact of breastfeeding on recovery from PPCM remains controversial. Given that bromocriptine causes cessation of lactation, women with PPCM who want to continue breastfeeding are excluded from the randomized trial. This proposal will follow 50 such women and investigate the levels of these biomarkers and whether the recovery of left ventricular function differs in breastfeeding women. REBIRTH will clarify the role of bromocriptine for the treatment of this disorder. This proposal will also evaluate the impact of breastfeeding, and will have a significant impact on the overall management of women with PPCM.