Abnormal testicular descent is fairly common (30% among premature babies and 1-4% of full term babies). It a major risk factor for infertility later in life. If you are having trouble conceiving, it might be worth poking into your past a little bit to see whether or not you had any early issues.
During fetal development, male gonads descend from their starting point on the posterior abdominal wall (the back of the inside of your abdomen), moving near the kidneys, down the abdomen, and through the inguinal canal into the scrotum. Cryptorchidism, or a testicle that has not yet descended into the scrotum at birth, is one of the most common congenital conditions in the pediatric population. It’s most common in pre-term births (30%) and comparatively not as common in full-term births (1-4%). The testicle may descend on its own, or medical intervention may be required if it does not. Cryptorchidism is the most common factor in the cause of adult azoospermia.
As an adult man, you may or may not be aware of having an “empty scrotum” when you were born. Either way, it may be affecting your fertility now. Cryptorchidism, especially if not treated properly, frequently results in impaired germ cell maturation, which results in infertility as an adult. If you are having difficulty conceiving, it might be worth an awkward conversation with your mom to find out if you were one of the male babies born before his testicle descended.
Also, men born with an undescended testicle have an increased risk of testicular cancer later in life, in both testicles, but even more so if the undescended testicle never descended, in part because it’s harder to examine the testicle and therefore detect malignant lesions. An untreated, undescended testicle can also increase the risk of testicular torsion (ow! Seriously, no one wants this. Do not ask.).
What to ask yer mom
If you were born with an undescended testicle, both timing and intervention matter.
- Did the testicle descend at all?
- If so, did it descend on its own?
- When (in months)?
- If it needed help, when was intervention performed?
Six months is about when the doctors should stop waiting and start prodding, because after this point a testicle is unlikely to descend on its own—and the marginal improvements to fertility are significant.
In most cases the testicle descends on its own (whew!).
If not, first-line treatment is hormone injections (human chorionic gonadotropin (HCG),gonadotropin (LH)-releasing hormone (GnRH, LHRH), testosterone, or a combination of therapies) to try to coax the testicle into the scrotum. These therapies have limited (less than 25%) and predetermined success rates, as effectiveness depends on the position of the testis at the outset of treatment. A more effective (greater than 80%) but more invasive approach is orchiopexy—surgery to move the testicle into the scrotum. However the testicle comes down, just bringing it into the scrotum can increase sperm production and improve fertility.
As in all things, there are complications and special circumstances worth mentioning.
Although it’s less common, sometimes neither testicle is descended at birth. If it’s just oneunilateral cryptorchidism, the incidence of azoospermia is 13%. If it’s both, or bilateral cryptorchidism, this figure goes up to a whopping 89% of men. This is actually great news, because it means that a descended testicle can pick up some of the slack for an undescended testicle. Take heart, unis!
The Case of the Missing Testicle
Sometimes surgery reveals that there is no testicle at all. This is a different congenital condition altogether: vanished or absent testis.
Other conditions that should be ruled out, preferably before treatment, are retractile testes (the doctor cannot find the small testicles due to a muscle reflex that retracts them; the testicles will descend and grow at puberty, and surgery is not needed) and ectopic testis (a testicle that wanders off and ends up in a different part of the body than the scrotum).
It’s not always easy to tell. About 80% of undescended testicles are “palpable” (can be felt in the abdominal wall through the scrotum), with the other 20% “non-palpable.” Most that are palpable are located along the inguino-scrotal region; in other words, it had almost reached the scrotum before birth. Non-palpable undescended testicles may be found in the abdomen, just before or after reaching the inguinal canal. Boys born with abdominal testes are more likely to have ductal abnormalities and testicular maldevelopment.
The testicle that never descended
If your undescended testicle is discovered later in life, your doctor may recommend removal. If they don’t descend, they don’t work too well. And we already covered the cancer risk.
- Fertility Potential in a Cohort of 65 Men with Previously Acquired Undescended Testes. Brakel, Jocelyn Van, Ries Kranse, Sabine M.p.f. De Muinck Keizer-Schrama, A. Emile J. Hendriks, Frank H. De Jong, Wilfried W.m. Hack, Laszla M. Van Der Voort-Doedens Rn, Chris H. Bangma, Frans W. Hazebroek, and Gert R. Dohle. (2013).
- Cryptorchidism – Disease or Symptom? Toppari, J., W. Rodprasert, and H. E. Virtanen. (2014).
- Cryptorchidism: A Clinical Perspective. Kollin, C., and E. M. Ritzén. (2014).
- Cryptorchidism and Testicular Cancer: Separating Fact From Fiction. Wood, Hadley M., and Jack S. Elder. 181.2 (2009): 452-61.
- Age at Surgery for Undescended Testis and Risk of Testicular Cancer. Pettersson, Andreas, Lorenzo Richiardi, Agneta Nordenskjold, Magnus Kaijser, and Olof Akre. (2007): 1835-841.
- Importance of Early Postnatal Germ Cell Maturation for Fertility of Cryptorchid Males. Hadziselimovic, F., and B. Herzog. 55.1 (2001): 6-10.
- The absent cryptorchid testis: surgical findings and their implications for diagnosis and etiology. Turek, P. J., D. H. Ewalt, H. M. Snyder, D. Stampfers, B. Blyth, D. S. Huff, and J. W. Duckett. Mar. 1994. Web.