Abstract
A woman in her 30s at 29 weeks of gestation was diagnosed with a fetal abdominal cyst and polyhydramnios. As the cyst gradually increased in size, an elective caesarean section was performed at 38 weeks of gestation. The neonate experienced respiratory distress due to tense abdominal distension shortly after birth. An emergency laparotomy was performed. The intestinal tract was markedly dilated and contiguous with the cyst. The small bowel distal to the dilated intestine had herniated through the defect. The dilated segment was resected, and an ileostomy was created. The operative and histopathological findings suggested segmental dilatation of the intestine (SDI). SDI is a rare gastrointestinal disorder presenting during the neonatal period. It can cause respiratory failure in newborns by compression owing to its large size. SDI should be considered in the differential diagnosis of relatively large abdominal cysts, and collaboration with paediatric surgeons and neonatologists is necessary for successful outcomes.