The Pros and Cons of Spaying and Neutering an Older Dog

Spaying and neutering are surgical procedures that involve the removal of reproductive organs in female and male dogs, respectively. These procedures are usually done when dogs are young—between 6 and 15 months of age, depending on the dog’s breed.

Yes, many older dogs can be spayed or neutered, but age alone is not the deciding factor.

There’s no definitive cutoff age for spaying or neutering a dog, says Scott Pendleton, DVM, veterinarian at Heritage Veterinary Care in Hopedale, Ohio. Instead, the dog’s overall health is the main factor in determining whether they are a good candidate for these surgeries.

As dogs age, they might develop certain health issues that could make surgery (and the required anesthesia) riskier. Health problems such as heart disease, kidney issues, or respiratory problems can complicate anesthesia and the recovery process.

Because of this, conducting a thorough pre-surgical exam, including blood work, is crucial to assess a dog’s fitness for surgery.

There isn’t a specific point when it becomes too late to neuter a dog. While the surgery is ideally performed when a dog is young and healthy, many older dogs are neutered without issue.

Instead of a blanket age or life stage that’s considered “too late,” veterinarians assess each dog individually to decide whether anesthesia and surgery are safe. In general, most healthy adult dogs can undergo neuter surgery safely.

If you adopt a senior dog who isn’t neutered, your vet can help you decide whether the benefits of surgery outweigh any risks.

There also isn’t a specific age when it’s too late to spay a female dog. Your veterinarian will perform pre-operative testing to assess your dog’s health and determine whether they’re a good candidate for surgery.

If you have an intact senior dog, they may have health conditions that increase the risk of complications. In this case, your vet can help you decide whether surgery is a good idea.

When deciding whether to spay or neuter an older dog, it’s important to weigh the pros and cons.

According to Paige Adams, DVM, veterinarian at Etowah Veterinary Hospital in Marietta, Georgia, spaying or neutering an older dog offers several health benefits:

• Reduced risk of certain cancers: Spaying in female dogs eliminates the possibility of uterine and ovarian cancer and significantly reduces the risk of mammary cancer. Neutering in males eliminates the risk of testicular cancer. Spaying and neutering can also eliminate other types of cancer in dogs when caught early.
• Prevention of pyometra: Pyometra is a severe and often life-threatening uterine infection that can occur in female dogs. It results in the accumulation of pus in the uterus, leading to symptoms such as lethargy, increased thirst, fever, and abdominal swelling. If an older female dog has not yet developed pyometra, spaying can remove the risk altogether. If they’ve already developed the condition, spaying can often cure it, especially if caught early.
• Reduced risk of benign prostatic hyperplasia (BPH): Intact older male dogs often develop noncancerous enlargement of the prostate gland, known as BPH. Symptoms can include difficulty urinating, bloody urine, and constipation. Neutering prevents this condition from occurring and can reduce the symptoms if the condition has already developed.
• Prevention of hernias and perianal tumors: Intact older male dogs can develop perianal tumors near the rectal area. These can be painful and may require surgical removal. Hernias (protrusions of an organ through an abnormal opening in the muscle or tissue) can also develop. Neutering can significantly reduce the incidence of these conditions.

The vast majority of geriatric patients (older dogs in the last 20% of their lifespan) are spayed or neutered for therapeutic reasons. For male dogs, neutering is almost always done for prostate problems. In females, geriatric dogs are most commonly spayed due to pyometra or cycle irregularities.

Male dogs, regardless of age, have innate behaviors linked to their reproductive status. When intact, male dogs are more likely to:

• Mark territory: Marking with urine is a way to communicate with other dogs about their presence. This behavior can be seen inside the home or on virtually any object or space the dog deems worthy of marking.
• Wander: An intact male dog can be compelled to roam in search of a mate. This behavior can increase the risk of accidents, getting lost, or potential altercations with other animals.
• Pester female dogs: Intact male dogs can be particularly persistent when it comes to female dogs, especially those who are unspayed. While out in public, they might engage in behaviors such as persistent sniffing, following, or attempting to mount the females. This behavior can be bothersome and distressing for both the female dogs and their pet parents.
• React: Hormonal surges can sometimes result in heightened reactivity behaviors, leading to conflicts with other dogs or even risky situations with humans.
• Mount: Intact males often display mounting (aka humping) behaviors. This can be directed at other animals, objects, or even people.

Neutering can significantly diminish or eradicate these behaviors, making your dog more manageable and reducing risks associated with these actions.

Although a male dog’s sperm count decreases with age, most can breed until they die.

Female dogs can still get pregnant into their senior years. However, at this old age, female dogs often have serious complications during pregnancy or labor that put their lives and their pups’ lives at risk.

Health issues aside, not spaying or neutering your dog can lead to unwanted litters that contribute to the overpopulation of dogs. This means more animals wind up in shelters.

Spaying or neutering is a responsible step to ensure no unexpected litters occur, benefiting both the individual dog and the broader canine community.

Unspayed female dogs go through an estrous cycle, commonly referred to as “going into heat.” During this cycle, which usually occurs about twice a year, they experience a phase called estrus.

Estrus is when a dog is receptive to mating, and they often exhibit a bloody vaginal discharge. This discharge can sometimes be quite noticeable and require pet parents to take extra precautions to manage the mess, including using special doggy diapers or restricting the dog to certain areas of the home.

By spaying a female dog, this estrous cycle is eliminated along with the associated bleeding, providing relief from the periodic mess for pet parents.

According to a 2013 study from the University of Georgia that analyzed over 70,000 animal medical records, neutered male dogs lived approximately 14% longer than their unaltered counterparts, and spayed female dogs lived about 26% longer.

To put this in context, intact dogs had an average lifespan of 7.9 years, whereas altered (spayed and neutered) dogs lived up to an average of 9.4 years.

While spaying or neutering requires an upfront cost, it’s an investment that can lead to financial savings in the long term. This is because the procedures:

• Prevent reproductive system-related diseases and can save on hefty medical bills that arise from treatments, surgeries, or long-term care associated with these conditions.
• Avoid unintended litters, which eliminates costs associated with prenatal care, birthing, and puppy care.
• Reduce reactivity and wandering behaviors, which can mean fewer expenses related to injuries, lost-dog recoveries, or property damage.

While spaying and neutering come with lots of benefits, there are things to consider, too.

“Anesthesia, and surgery itself, is always a risk,” Dr. Adams says. “Even if we do all of the pre-operative planning, blood work, etc., there is an inherent risk.”

General risks associated with anesthesia range from vomiting after waking up to life-threatening cardiac arrest. With surgery, some general risks can include infection, opening of the surgery site, and excessive bleeding.

While these risks are low, older dogs might have heightened vulnerabilities, says Dr. Adams.

When older dogs with aging organs undergo anesthesia, complications can arise because their bodies might not process or eliminate the anesthetic agents as efficiently. This can result in delayed awakening and increased post-operative confusion. Wounds might also heal more slowly in older dogs.

Additionally, pre-existing conditions such as heart disease or respiratory issues can complicate the surgical procedure. These conditions may remain undetected until the dog undergoes surgery, leading to unexpected challenges.

Given these potential complications, it’s crucial for a veterinarian to conduct a thorough pre-surgery evaluation on an older dog. With careful planning, these risks can be greatly minimized.

One considerable con is weight gain. The surgery can slow a dog’s metabolism, causing weight accumulation.

“Older dogs will almost always gain 10–20% of their body weight after being spayed or neutered,” says Dr. Pendleton.

Because of this, pet parents should be ready to modify their dog’s exercise and diet accordingly. Switching to a weight-control dog food, like Hill’s Science Diet Adult Perfect Weight Chicken Recipe Dog Food, might help.

After spaying or neutering, some dogs experience alterations in their coat, Dr. Adams says. Some dogs’ coats may become thinner, while others may find the coat becomes thicker.

Not every dog undergoes these changes, and it’s not always a bad thing—just something to be aware of.

Older dogs may take a little longer to heal from the surgical procedure than their younger counterparts, especially with a spay because it’s more invasive.

General guidelines suggest that pet parents should restrict their dogs’ exercise for 10–14 days after the surgery. Older dogs might take the full 14 days to recover—or even a bit longer.

This may be partly because older dogs have larger reproductive systems than puppies and, as a result, require larger incisions, which take longer to heal, Dr. Adams says. In general, older dogs also heal a bit more slowly than younger dogs.

The cost of spaying or neutering can be a concern for pet parents. The immediate expense can be substantial, particularly when the procedure is conducted at specialized veterinary clinics or if the dog requires extra health precautions.

However, as noted before, the procedure can result in long-term savings by preventing future medical expenses associated with reproductive complications or unintended pregnancies.

No, neutering an older dog (or a dog of any age) will not make them calmer or change their overall energy level or playfulness. However, spay or neuter surgery may have behavioral benefits, such as reducing unwanted behaviors like marking, mounting, and reactivity.

Neutering can be a little harder on older dogs, but the side effects are typically still minimal. Older dogs may wake from surgery more slowly and have a slightly longer recovery time than younger dogs.

A pre-surgical exam, blood work, and your veterinarian’s thorough review of your dog’s overall health and medical history can help determine whether a spay or neuter procedure is safe and appropriate.

No, neutering or spaying an older dog—or a dog of any age—typically doesn’t alter their personality.

However, behaviors associated with testosterone (in males) or estrous cycles (in females) may decrease or disappear post-surgery—including behaviors like wandering, reactivity, and excessive marking of territory in males—and temperamental behavior (when in heat) in females.