Conclusion  We believe that the incidence is still too low to recommend routine contralateral exploration. Therefore, infants younger than 18 months appear to be a higher-risk subpopulation and should receive closer follow-up over this time period. Content Type Journal ArticleCategory Original ArticleDOI 10.1007/s10029-009-0537-7Authors M. Jallouli, Hedi Chaker Hospital Department of Pediatric Surgery 3029 Sfax TunisiaS. Yaich, Hedi Chaker Hospital Department of Epidemiology 3029 Sfax TunisiaM. B. Dhaou, Hedi Chaker Hospital Department of Pediatric Surgery 3029 Sfax TunisiaH. Yengui, Hedi Chaker Hospital Department of Pediatric Surgery 3029 Sfax TunisiaD. Trigui, Hedi Chaker Hospital Department of Pediatric Surgery 3029 Sfax TunisiaJ. Damak, Hedi Chaker Hospital De...