INTRODUCTION: Long-term treatment with parenteral nutrition (PN) may be essential for survival in infants after neonatal gastrointestinal surgery. It seemed well indicated in a population-based study to estimate the need for long-term PN and to characterize the infants that received TPN with regard to diagnosis and clinical course. METHODOLOGY: This study reviews the clinical course of infants with gastrointestinal disease (gastroschisis, intestinal atresia, omphalocele, volvulus, Hirschsprung's disease and necrotizing enterocolitis) with a prolonged need for parenteral nutrition in the Western part of Denmark over a period of 11 1/2 years. RESULTS: A total of 21 patients with need for PN for 55 days or more due to gastrointestinal disease were registered with a cumulative hospital stay of 4462 days. The study showed a low incidence of long-term PN due to gastro-intestinal surgical illness with an incidence of approx 6.1 per 10(5) births per year. Gastroschisis and intestinal atresia were the most common primary diagnoses. Two groups of patients were identified: 1) six infants with short gut syndrome caused by major resections or atresia of the small intestine (less than 50 cm intestine) and 2) a larger group (n = 15) with no or only minor resection of the small bowel. The former group had a significantly longer hospital stay and a longer need for PN. The incidence of short bowel syndrome including six infants was 1.7 per 10(5) births per year. CONCLUSIONS: Prolonged need for PN in infants operated for gastrointestinal disease was registered at a low frequency in the Western part of Denmark, most frequently caused by gastroschisis and intestinal atresia. The clinical course was characterized by repetitive problems of catheter replacements and septic episodes. The mortality due to conditions related to the gastrointestinal disease was 14% (3/21).