sentences:  There is good but not ideal evidence that circumcision of babies reduces the incidence of UTIs in boys under two years of age, and there is fair evidence that the reduction in incidence is by a factor of 310 times (100 circumcisions prevents one UTI).Circumcision is most likely to benefit boys who have a high risk of UTIs due to anatomical defects, and may be used to treat recurrent UTIs.There is a plausible biological explanation for the reduction in UTI risk after circumcision.