Cryptorchidism is a developmental condition in which one or both of a male dog’s testicles fail to descend into the scrotum, remaining instead in the abdomen or inguinal canal. It is one of the most common congenital defects seen in dogs, affecting an estimated 1 to 10 percent of males depending on the breed, and while an undescended testicle rarely causes symptoms on its own in a young puppy, the condition carries meaningful long-term health risks that make early diagnosis and treatment important.
What Causes Cryptorchidism
During normal fetal and early puppy development, the testicles form near the kidneys and gradually migrate down through the abdomen and inguinal canal into the scrotum, typically completing this descent by around 6 to 8 weeks of age, though it can occasionally continue up to around 6 months. Cryptorchidism occurs when this migration is incomplete, leaving one testicle (unilateral) or both testicles (bilateral) retained somewhere along the pathway, either in the abdomen or inguinal canal. The condition is considered hereditary, and because affected males can still be fertile if one testicle descended normally, veterinarians strongly recommend against breeding dogs with cryptorchidism to avoid passing the trait to future generations.
Which Breeds Are More Commonly Affected
While cryptorchidism can occur in any breed, certain breeds show a higher prevalence, including Yorkshire Terriers, Poodles, Pomeranians, Chihuahuas, Boxers, Dachshunds, and Shetland Sheepdogs, among others, suggesting a genetic component within specific lines. Toy and small breeds are generally overrepresented compared to larger breeds. A veterinarian typically checks for testicular descent during routine puppy wellness visits starting around 8 weeks of age, and if both testicles are not palpable in the scrotum by roughly 6 months, a diagnosis of cryptorchidism is usually confirmed, since spontaneous descent after this age is uncommon.
Health Risks of Retained Testicles
Retained testicles are significantly more prone to developing testicular cancer later in life compared to normally descended testicles, with some studies suggesting the risk may be substantially higher, particularly for Sertoli cell tumors and seminomas. Retained testicles are also at increased risk of testicular torsion, a painful twisting of the testicle that cuts off its blood supply and requires emergency surgery. Additionally, dogs with cryptorchidism have a higher documented association with other reproductive abnormalities. Because a retained testicle sits at an abnormally warm internal body temperature rather than the cooler environment of the scrotum, the elevated cancer and torsion risks are thought to be linked to this temperature difference.
Diagnosis and Surgical Treatment
Diagnosis usually starts with a physical exam to check whether both testicles can be felt in the scrotum, and if one or both are missing, ultrasound or abdominal imaging can help locate a retained testicle before surgery. Because of the elevated cancer and torsion risks, veterinarians almost universally recommend neutering dogs with cryptorchidism, which involves removing both testicles, including surgically retrieving any retained testicle from the abdomen or inguinal canal. This procedure is more involved than a standard neuter since it may require an abdominal incision to locate and remove an internally retained testicle, but it is generally well tolerated and resolves the associated health risks going forward.
Timing and Long-Term Outlook
Most veterinarians recommend neutering a dog with confirmed cryptorchidism once it is clear the testicle will not descend on its own, often around 6 months of age, both to eliminate the future cancer and torsion risks and to prevent the dog from being used for breeding. Dogs who undergo timely surgical correction generally go on to live completely normal, healthy lives with no lasting complications from the condition itself. Because cryptorchidism has a hereditary component, breeders are advised to avoid breeding not only the affected dog but also, where known, close relatives with a history of the condition, to help reduce its prevalence in future litters.
Frequently Asked Questions
At what age is cryptorchidism diagnosed in dogs?
Veterinarians typically check for testicular descent starting around 8 weeks of age, with a formal diagnosis usually confirmed if both testicles are not palpable in the scrotum by about 6 months, since spontaneous descent after that point is uncommon.
Is cryptorchidism painful for dogs?
The condition itself is not typically painful in a young dog, but retained testicles carry a higher risk of testicular torsion, which is acutely painful and requires emergency surgery if it occurs.
Do cryptorchid dogs need to be neutered?
Yes, neutering is almost universally recommended because retained testicles have a significantly higher risk of developing cancer later in life, and surgery removes this risk along with preventing the dog from breeding.
Can a cryptorchid dog still get a female pregnant?
Yes, if at least one testicle has descended normally and is producing viable sperm, a cryptorchid dog can still be fertile, which is one reason veterinarians recommend neutering rather than leaving the condition unaddressed.
Is cryptorchidism genetic?
Yes, it is considered a hereditary condition, and affected dogs, along with their close relatives where known, are generally advised not to be used for breeding to help reduce the trait in future generations.