Veterinarian-written / veterinarian-approved articles for your dog.

Cryptorchidism: Retained Testicles in Dogs

Retained testicles are common in dogs.

Cryptorchidism means that one or both testicles have failed descend out of the abdomen where it was in utero.

Causes of Cryptorchidism in Dogs

Both testicles should descend into a dog's scrotum by at least four months after birth (and usually much earlier). If one or both hasn't done so, it is considered to be retained.

A testicle may be retained in the inguinal area, which is in the groin, or higher up, still within the abdomen.

This condition is considered to be genetic. It occurs in all dog breeds but is more common in toy breeds.

Signs of Cryptorchidism in Dogs

There are rarely any signs of the condition other than the veterinarian identifying only one or no testicles in the scrotum. It does not cause pain or any signs of illness in the dog.

If the retained testicle(s) is inguinal, the doctor can usually feel it there. If it's abdominal, the doctor can't feel it at all.

Cryptorchidism often occurs concurrently with other inherited conditions like luxating patella.

Diagnosis of Cryptorchidism in Dogs

Diagnosis of cryptorchidism is made through a physical exam. The doctor checks the scrotum for two testicles and can feel if one or both are missing.

If the dog is a stray, missing testicles may simply indicate that he has been castrated. If that is suspected, an hCG stimulation test can be done. An injection is given, and blood testosterone levels are tested before and afterward. A dog that has retained testicles will show a much higher testosterone level on the post-injection blood sample than on the pre-injection sample.

Ultrasound may help identify a testicle within the abdomen.

Treatment of Cryptorchidism in Dogs

There is no treatment for this condition other than surgical removal of the testicles. For dogs with abdominally retained testicles, that will involve opening the abdomen to search for and remove them.

Castration surgery should be done because retained testicles are at a much higher risk of developing cancer (around 10x higher than dogs with testicles in the scrotum).

You May Also Like These Articles:

Prostate Infection in Dogs: Prostatitis

Dog Neutering: Is Earlier Better?

Sexual Behavior in Neutered Dogs

Luxating Patella in Dogs

Ultrasound: What Is It and When Do Vets Use It?

Disclaimer: This website is not intended to replace professional consultation, diagnosis, or treatment by a licensed veterinarian. If you require any veterinary related advice, contact your veterinarian promptly. Information at is exclusively of a general reference nature. Do not disregard veterinary advice or delay treatment as a result of accessing information at this site. Just Answer is an external service not affiliated with

Notice: Ask-a-Vet is an affiliated service for those who wish to speak with a veterinary professional about their pet's specific condition. Initially, a bot will ask questions to determine the general nature of your concern. Then, you will be transferred to a human. There is a charge for the service if you choose to connect to a veterinarian. Ask-a-Vet is not manned by the staff or owners of, and the advice given should not delay or replace a visit to your veterinarian.