We reviewed the final diagnosis and incidence of bowel pathology in neonates presenting with large bowel obstruction that was relieved by the passage of meconium plugs. A retrospective case-note review was undertaken of all patients with a discharge diagnosis of meconium plug syndrome (MPS), meconium ileus (MI), Hirschsprung’s disease (HD), or small left colon syndrome (SLCS) from January 1996 to April 2002. Of 21 patients with meconium plug obstruction, eight (38%) had HD, nine had MPS, four had SLCS, and none had MI. However, there was considerable clinical and radiological overlap between MPS and SLCS, suggesting that these terms are imprecise. We found a much higher incidence of HD in babies presenting with meconium plug obstruction than has previously been reported. Overlap between MPS and SLCS suggests that these are not specific diagnoses and that current terminology needs to be changed. All babies with meconium plug obstruction should have HD and cystic fibrosis (CF) excluded.