Surgical sterilization is a procedure that provides permanent and definitive contraception. It involves removing both testicles in males and both ovaries (and sometimes the uterus) in females. This technique requires general anesthesia, typically short-lasting as the procedure is well-controlled by veterinarians. Complications are rare.
Neutering Your Pet Offers Many Benefits for Both Males and Females:
The Benefits of Spaying in Females
Beyond preventing uncontrolled reproduction (which leads to unwanted litters and euthanasia) and eliminating heat cycles—often unpleasant for those around them (roaming and bleeding in dogs, yowling and hypersexualized behavior in cats)—ovary removal helps prevent the development of several reproductive system diseases. This includes ovarian conditions (such as cancers), uterine disorders (like pyometra, a uterine infection), and mammary issues (particularly mammary tumors, but also potential mastitis, a complication of pseudopregnancy or "false pregnancy," which can occur in dogs). These conditions are relatively common in intact (unspayed) females and often fatal: mammary tumor-related mortality is around 50% in dogs and 90% in cats! Several scientific studies have also shown that spaying increases their lifespan.
The Benefits of Neutering in Males
Like in females, neutering helps reduce the risk of reproductive system diseases, such as testicular cancer and various prostate conditions (including hyperplasia, cysts, or abscesses).
This procedure also helps reduce sexual behaviors, including urine marking and aggression. It’s worth noting that, particularly in cats, neutering decreases the frequency of fights between peers, thereby lowering the risk of transmitting various infectious diseases, such as Feline Immunodeficiency Syndrome caused by FIV (Feline Immunodeficiency Virus), also known as feline AIDS.
Finally, sterilization—whether for males or females—enables better population control.
Are There Any Downsides or Risks to Sterilization?
Sterilization is an irreversible procedure: it’s therefore essential to be certain, before making your decision, that you won’t want your four-legged companion to reproduce once they reach adulthood.
General anesthesia does come with risks, as with any procedure or operation requiring your pet to be put under. For spaying, however, the risks are relatively low in a healthy animal, as your vet will follow a well-controlled anesthetic protocol. The surgery itself is usually short (though it takes longer for larger-breed dogs), so any potential side effects of general anesthesia are minimized.
Studies have shown that in both dogs and cats, and in females as well as males, neutering increases the risk of obesity. A controlled diet can help minimize this risk. Your vet will most likely recommend new kibble after surgery, better suited to your pet’s altered metabolism. Also, ensure your pet gets daily physical activity. Often, libido, mounting behaviors, and urine marking are reduced in dogs after castration. However, if such behaviors are learned, surgery may not resolve the issue. It’s important to discuss this during the puberty consultation. If your dog is affected, your vet may suggest starting with reversible medical castration.
Recent studies suggest a link between sterilization and an increased risk of developing:
- Certain cancers, such as lymphoma or mast cell tumors;
- Certain orthopedic conditions, including hip or elbow dysplasia and cranial cruciate ligament rupture—particularly common in large-breed dogs;
- Certain endocrine disorders, such as hypothyroidism or hyperadrenocorticism (in ferrets, a link between adrenal disease and neutering has been established).
- Urinary incontinence, especially in female dogs
Studies have shown that the significance of these associations varies considerably by breed, sex, and age during sterilization. This naturally raises the question of whether surgery to remove healthy organs is justified. It is therefore essential to discuss all of this during a consultation dedicated solely to this topic with your attending veterinarian, weighing the pros and cons from a medical standpoint while considering your four-legged companion’s lifestyle and social aspects. Your veterinarian is best placed to advise you and provide the most relevant insights.
Sources:
Pet Owner Resources: Find AAHA’s expert guidelines on this page.
Frequency, breed predisposition, and demographic risk factors for overweight status in dogs in the UK: This study published in the *Journal of Small Animal Practice* aimed to assess the prevalence and risk factors for obesity in dogs.
Supporting Neutering Age Decisions for Mixed-Breed Dogs Across Five Weight Categories: Associated Joint Disorders and Cancers – Supporting Neutering Age Decisions for 35 Dog Breeds: Associated Joint Disorders, Cancers, and Urinary Incontinence: These literature reviews provide recommendations for determining the optimal age for neutering specific dogs, based on size or breed, and sex.
Links Between Early Neutering, Obesity, Outdoor Access, Trauma, and Feline Degenerative Joint Disease: This study aimed to identify various factors associated with the onset of osteoarticular disorders in cats.
