What do I do about an undescended testicle?

Please visit a urologist in your area. Newborns may have an undescended testicle but almost all boys should have it drop to the scrotum by one year of age. An undescended testicle at an older age has an increased chance of cancer later in life. But this does not mean it will become cancerous. If the testicle were in the scrotum it would continue to function and you could check periodically to see if a cancer were developing. If you are older than one year and have an undescended testicle then you should definitely see a urologist in your area to either perform orchiopexy to put it down in the scrotum, or have orchiectomy to remove it. Which one is right depends on factors you can discuss with your urologist.