Ninety-six couples, consulting for primary (n = 73) or secondary (n = 23) infertility, and thought to be infertile due to a varicocele in the husband associated with sperm abnormalities, were subjected to a follow-up study. Of these, 57 were surgically corrected and 39 were not, depending only on the patient's choice. All women were intensively treated where necessary. From our data we conclude that (1) fertility prognosis is significantly better in couples with secondary subfertility than in couples with primary subfertility, (2) surgical correction of varicocele in cases of secondary subfertility does not increase subsequent pregnancy rates, and (3) surgical correction of varicocele in cases of primary subfertility significantly increases subsequent pregnancy rates, since cumulative observed pregnancy rates are more than double the cumulative theoretically expected treatment-independent pregnancy rates.