The objective of this work was to explore the impact on parents of the bronchiolitis hospitalization of their infant using the Impact of Bronchiolitis Hospitalization Questionnaire (IBHQ©). METHODS: Four hundred sixty-three infants aged less than 1 year and hospitalized for bronchiolitis were included in a French observational study during the 2008-2009 season. Parents were asked to complete the IBHQ at hospital discharge and 3 months later. IBHQ scores, ranging from 0 (no impact) to 100 (highest impact), were compared according to gestational age (full-term, 33-36 wGA, ≤ 32 wGA) and the presence of congenital heart disease (CHD). The potential drivers of impact were explored using multivariate linear regressions. RESULTS: The study included 332 full-terms, 71 infants born at 33-36 wGA, and 60 at ≤ 32 wGA; 28 infants had a CHD. At hospital discharge, 9 of the 12 IBHQ mean scores were above 40, indicating a marked impact on parents. Three months later, all mean scores were lower but 5 were still greater than 40. At discharge, the length of hospitalization had a significant effect on IBHQ worries and distress, fear for future, guilt and impact on daily organization scores (p\textless0.01); the parents' educational level had a significant effect on IBHQ worries and distress, fear for future, impact on daily organization and financial impact scores (p\textless0.05). The only statistically significant difference found between the parents of preterm and full-term infants was for the physical impact score at discharge (p=0.004). CONCLUSIONS: Bronchiolitis hospitalization has conspicuous emotional, physical and organizational consequences on parents and siblings, which persist 3 months after hospital discharge. The main drivers of the impact were length of hospital stay and parents' educational level, while infants' gestational age or the presence of a CHD had little influence.