To gain further insight into the natural history of patients with biliary atresia. We performed a retrospective, cross-sectional, descriptive, case series study. All patients with biliary atresia attended at the Pediatric Gastrointestinal and Hepatology Unit of La Fe Children's Hospital in Valencia (Spain) from January 1990 to December 2000 were included. Of 16 children followed-up, eight are currently stable, six have undergone liver transplantation and two died. The mean age at diagnosis was 47.5 days. The most frequent clinical manifestation was jaundice (87.5%) and the most common biochemical finding was raised gamma-glutamyltransferase (3-4 times its standard value), which appeared in 100 % of the patients. Abdominal ultrasonography was diagnostic in 85.7% of the patients. Nuclear scintiscan (DISIDA) showed a sensitivity of 100%. Portoenterostomy with intraoperative liver biopsy was performed in all patients. Patient age at surgery was a predictor of long-term outcome, with more favorable results in patients aged less than 65 days of life. Biliary atresia should be suspected as soon as possible, since early surgical treatment is the only therapeutic measure that can improve outcome.