In PPCM mice, a cardiomyocyte‐specific knockout for STAT3 (conditional knockout [CKO]), cardiac PAI‐1 as a binding partner of 16‐kDa PRL, its expression was higher than in postpartum wild‐type controls, whereas a systemic PAI‐1‐knockout in CKO mice accelerated peripartum cardiac fibrosis, inflammation, heart failure, and mortality.64 The gene discussed is PRL; the disease is heart failure.