Age at diagnosis is a modifiable risk factor in outcomes after hepatoportoenterostomy in biliary atresia; however, distinguishing biliary atresia from other more common causes of prolonged neonatal jaundice can be difficult. To focus attention on diagnosis of biliary atresia, we analyzed secular trends in the age at diagnosis, and other factors that might influence outcome. We performed a retrospective analysis of 55 consecutive infants with biliary atresia presenting to a single academic pediatric center over 15-year period from 1990 to 2004. The median age at diagnosis was 60 days (range: 21-152). In recent era (2000-2004), the median age was 69.0 days, compared with 48.5 days (1990-1994) and 59.5 days (1995-1999), respectively. Consistent with previous studies, the median age at diagnosis of those with poor outcomes (death or liver transplant) exceeded those with good outcomes after the hepatoportoenterostomy (72 vs 52 days, P < .001). The lack of improvement, or a concerning trends toward an increase in the age at diagnosis of biliary atresia, is perhaps attributable to neonatal follow-up practices. Efforts to make an earlier diagnose of this important condition deserve wider application and study.