Polymyositis (PM) is an uncommon inflammatory myopathy that affects striated muscles. It causes weakness of the limb girdles, neck, and pharyngeal muscles. We are presenting a case of PM which manifested after intrauterine death (IUD). The patient was referred to our hospital for breathing difficulty, 4 days after delivery of a dead fetus. Initially, she was treated in line of puerperal sepsis and peripartum cardiomyopathy. Patient's cardiopulmonary functions improved but she had persistent high-grade fever. Gross muscle weakness was found on day 5 of admission, involving all four limbs, predominantly in proximal muscles and she had dark colored urine. Laboratory tests revealed myoglobinuria, high serum creatine phosphokinase (CPK) levels, and high lactate dehydrogenase (LDH) levels. Polymyositis diagnosed on the basis of high CPK levels, magnetic resonance imaging (MRI) of cervical spine, electromyography (EMG), and muscle biopsy findings. We question, whether the PM could be pathogenically related to the pregnancy? Literature review of the previously reported cases of PM/dermatomyositis and our case report suggests that pregnancy can trigger the new onset of PM. [ABSTRACT FROM AUTHOR]