Tehran University of Medical Sciences Acta Medica Iranica 0044-6025 53 8 2015 10 06 518 522 EN Saeid Tarlan Department of Pediatric Surgery, School of Medicine, Qazvin University of Medical Sciences, Qazvin, Iran. Abolfazl Mahyar Department of Pediatric, School of Medicine, Qazvin University of Medical Sciences, Qazvin, Iran. Victoria Chegini Department of Pediatric, School of Medicine, Qazvin University of Medical Sciences, Qazvin, Iran. Venus Chegini Department of Gynecology, School of Medicine, Tehran University of Medical ScienceS, Tehran, Iran. 2015 10 06 2015 10 06 Megacystis Microcolon Intestinal Hypoperistalsis Syndrome (MMIHS) is a rare and the most severe form of functional intestinal obstruction in the newborn. The characteristic features of this congenital and fatal disease are abdominal distension, absent or decreased bowel peristalsis. Abdominal distension is a consequence of the distended, unobstructed urinary bladder with or without hydronephrosis. We present a case of female newborn with antenatal ultrasound revealing a large cystic mass in pelvic with urinary tract origin, abdominal distension, aperistalsis of the intestine and micro colon. https://acta.tums.ac.ir/index.php/acta/article/view/4281 https://acta.tums.ac.ir/index.php/acta/article/download/4281/4236