Hi, Testicular cancer. Testicular cancer usually begins in the cells in the testicle that produce immature sperm. What causes these cells to develop into cancer is unknown. Men who've had an undescended testicle have an increased risk of testicular cancer. The risk is greater for undescended testicles located in the abdomen than in the groin. Surgically correcting an undescended testicle might decrease, but not eliminate, the risk of future testicular cancer.Fertility problems. Low sperm counts, poor sperm quality and decreased fertility are more likely to occur among men who've had an undescended testicle. A decrease in cells in the testicle that produce sperm has been found as early as 1 year old.