Q: My 21-month-old son was born with undescended testicles. What is the chance his testicle will come down on its own?
A: A testicle which hasn't made its way into the scrotum by the time a child is 1 or 2 years old is unlikely to "come down" on its own. We can surmise this from studies which have been done comparing the number of undescended testicles in groups of male infants, boys and young men.
Two or three out of 10 boys born prematurely have undescended testicles at birth, most of which "come down" during the next few months. No more than one in 25 boys born at term have an undescended testicle. By 1 year of age, fewer than one in 100 do. It's about the same in young men, so we can conclude few testes come down on their own after the first year.
We would suggest it is time to assist your son's testicle in its trip from inside the abdomen where it was formed through the "inguinal canal" into the scrotum. To accomplish this his doctors will probably try special hormone injections for several weeks first. If the testicle doesn't appear, surgery to bring it down from the abdomen into the scrotum and fasten it there will be needed.
While injections and surgery may sound like a lot to put a small boy through, there are serious problems associated with undescended testicles that early intervention may help to avoid. Testes which remain in the abdomen do not develop properly. This abnormal development may be influenced by the higher body temperature there, but the cause may be more complicated than that. Having even one undescended testicle tends to lower the sperm count, though not always to the point of infertility. Most experts believe bringing the testicle into the scrotum during early childhood may help it to develop and function more normally.
Men with an undescended testicle also have a higher likelihood of developing testicular cancer. It is not clear whether bringing the testicle into the scrotum in early childhood will eliminate this extra cancer risk, but many surgeons are hopeful it will lower it. They point out that at the very least, a testicle in the scrotum can be examined and a cancer caught at the earliest stages. We want you to know about this cancer risk, but urge you not to panic. We think you need all this information to make an informed decision about your son.
Dr. Wilson is director of general pediatrics at the Johns Hopkins Children's Center; Dr. Joffe is director of adolescent medicine.