Sir.—The article by Gilhooly et al1 states that the overall fertility prospects in unilateral cryptorchidism were comparable with those of the population at large, thus giving an impression that the majority of patients with unilateral cryptorchidism should be spared of any treatment. However, a number of remarks to this statement should be considered.
1. The difficulty in diagnosing the cryptorchid state of the gonads is presented in the Figure where three different, large university centers participated. Nine hundred eighty-eight biopsy specimens obtained at surgery were analyzed. The vast majority of the children were unilateral cryptorchid and the position of their gonads were comparable. The percentage of those (unilateral or bilateral) cryptorchid boys lacking germ cells in their gonads differed significantly between the clinics, indicating that different criteria were utilized in determining the need for surgery. Our prospective study2 showed that a significant correlation exists between sperm quality