I have a single undescended testicle. this has been since birth. i frequently went to a pediatrician as a child who would check up but haven't been checked on after 8 years of age. is this a serious issue? i have a testicular us scheduled next month?

If a true undescended testis has not come down on its own or been surgically relocated before 2, the testis if present is a problem. The ultrasound can locate it in the abdomen, or there may not be one. If it is in the abdomen you would likely just have it removed as moving it down would be difficult. If memory serves me right, an abdominal testis has higher risks of cancer.

Undescended testicle can be classified as abdominal(non palpable) or inguinal (gliding). Congenital undescended testicle should be treated surgically no later than 15 months of age to prevent long term consequences, infertility, testicular malignancy, and torsion.

Nothing we can do about the past. It is urgent that you must see a Urologist right away- even before the ultrasound. Good luck