Pathologic gastroesophageal reflux encountered during the neonatal period can be associated with projectile vomiting often of bile stained gastric content. Between 1960 and 1979, symptomatic gastroesophageal reflux was diagnosed in 36 neonates. Duodenogastroesophageal reflux was present in 16 or 44.4% of this group. This abnormal phenomenon is classically encountered in our experience during the neonatal period. The in-series incompetence of the pyloric and lower esophageal sphincteric mechanisms gives rise to a variant of the so called phreno-pyloric syndrome. The seriousness of this association is emphasized in our series by the high incidence of complications encountered in the patients with this syndrome, i.e., gastroesophageal bleeding in 44% esophagitis with stricture of formation in 12.5%. Conservative management of the cases encountered with this syndrome was successful except in two cases where reflux esophagitis was complicated by severe stricture formation. It is postulated that the pathogenesis of this form of phreno-pyloric syndrome is most probably based upon a motility disturbance of the upper gastrointestinal tract, involving the hormone motilin.