After treatment, the testicle often grows to normal size in the scrotum. In some cases, the testicle wasn't normal to start with, and never grows the right way. In other cases, sperm never grow, even though the testicle size is normal. In most cases, after treatment for 1 undescended testicle, fertility becomes normal and the chances of fathering a child in the future are high. When the child becomes a teen, he should have routine physical exams and do monthly testicular self-exams. Routine physicals will look for signs of testicular cancer, which remains a slight risk.