The Pros and Cons of Spaying or Neutering Your Dog


Neutering refers to the surgery that renders a male pet incapable of reproducing. The surgery (orchiectomy) involves an external incision into the scrotal sac and the removal of the testicles. The testicles produce sperm and are the main source of the hormone testosterone.

Spaying refers to the surgery for a female pet. Surgical sterilization (ovariohysterectomy) involves an incision into the abdominal cavity to remove the ovaries and uterus. Ovaries produce eggs at each heat cycle and also produce the hormones estrogen and progesterone.

Veterinarians perform these common operations while the pet is under general anesthesia, during which the animal feels no pain. After the short surgery, the animal may experience discomfort as part of the normal healing process, however many animals, particularly males, seem to experience little or no discomfort. Your vet can provide pain relief medication if needed. Depending on the individual animal, he or she will stay at the vet’s office for a few hours or overnight. The pet is usually back to normal within several days.

Benefits for the pet:

Safety – neutered/spayed pets, especially males, are less likely to roam. When we spay or neuter pets, we are removing the hormones that feed the instinct to find a mate and reproduce. Sterilized animals are less driven to escape, wander and look for mates, and less likely to get hit by cars and get into fights with other animals while roaming in search of females in heat.

Health Benefits – Neutered males cannot develop testicular tumors, the second most common malignancy in males. The chance of developing an enlarged prostate is greatly reduced. Neutering also reduces the risk of rectal tumors and perianal fistulas.

Spaying the female eliminates the possibility of uterine, cervical or ovarian cancer. Spayed females have a much lower incidence of mammary tumors and breast cancer because the hormones, estrogen and progesterone, that stimulate breast cancer have been eliminated. An intact female has 7 times the risk of developing breast tumors as compared to a female spayed before her first heat cycle (six to nine months of age). Spaying also helps prevent uterine infections (pyometria).


Possible Health Risks:


• In large and giant breeds, neutering before one year of age may significantly increase the risk of osteosarcoma (bone cancer), a common cancer in these larger breeds.

• Increased risk of cardiac hemangiosarcoma.

• Although the risks are small to begin with, neutering can increase the risk of hypothyroidism, urinary tract cancers, prostate cancer, orthopedic disorders such as hip dysplasias. Increased risk of adverse vaccine reactions. Research suggests that the reproductive hormones may assist the immune system in mounting a response to vaccines.

• In large and giant breeds, spaying before one year of age may significantly increase the risk of osteosarcoma (bone cancer).
• Spaying may increase the risk of splenic and cardiac hemangiosarcoma, a common cancer in some breeds. Spaying may increase the risk of hypothyroidism, urinary tract infections, urinary “spay incontinence”, recessed vulva, vaginitis, orthopedic disorders such as hip dysplasias.
•There may be an increased risk of adverse vaccine reactions.

Benefits of spaying/ neutering for the community:

Tax-savings - Communities spend millions of dollars to manage the approximately 8-10 million abandoned animals taken in by public animal shelters. The cost of a spay or neuter surgery is less than the cost of one euthanasia at these shelters. 

Bettering the community – Dogs are domesticated and do not usually fair well on their own outside. It is very frightening and lonely to be an abandoned animal. Stray and homeless dogs may get into trash cans, defecate on private lawns, get sick, seek shelter under cars, frighten people, and possibly resort to biting out of fear. Spaying and neutering can reduce the number of animals born to suffer eventual homelessness. 

Improving society – Since there are not nearly enough homes for them all, approximately 4-6 million abandoned but loving and worthy animals die nationwide from euthanasia every year. This is a social tragedy that individual citizens can reverse by spaying and neutering their pets, and giving them a home for life.

When to spay and neuter:

When to and whether to spay and neuter your pet dog is a complex decision with respect to the associated long-term health benefits and risks. The evidence shows that spay/neuter correlates with both positive and adverse effects in dogs. It also suggests how much we really do not yet understand about this subject.

The traditional spay/neuter age of six months or younger appears to predispose dogs to health risks that could otherwise be avoided by waiting until the dog is physically mature.

The balance of benefits and risks of spay/neuter will vary from one dog to the next. Breed, age, and gender are variables that must be taken into consideration for each individual dog.

Choosing to keep your pet intact does not mean that you should allow him to breed.

Breeding should be done by only the most ethical, dedicated breeders who are thoroughly knowledgeable about heredity, genetics, health issues and testing, temperament, conformation, puppy rearing and placement, and the complete pedigree, history and traits of the individual dogs to be mated. These are NOT pet store breeders, puppy mills, or backyard breeders. They are people who raise and breed only the best to the best in order to improve the breed. They have qualified homes lined up for the puppies before breeding; they do not overbreed, and will always take back a dog if a placement doesn’t work out.

When you are considering spay/neuter, have an informed discussion with your vet about what the best option is for your particular dog.

Sue Sanders, Puppy Instructor
Great Companions
Member APDT

Great Companions LLC, Learn To Be Your Dog's Reward ™

Spaying & Neutering

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