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Is spaying/neutering the healthiest choice for my dog?

Is spaying/neutering the healthiest choice for my dog?

I never used to question the practice of spaying/neutering dogs and cats. My dog Ace was neutered before I adopted him, and I had my cats neutered because I thought that’s just what you’re supposed to do. I also knew it would likely decrease unwanted behaviors such as marking.

Today, I look at spaying and neutering differently.

In this post:

1. Whether or not to spay or neuter a pet is a personal choice, and I want pet owners to recognize that.

2. Spaying and neutering has potential health benefits as well as potential health risks. Pet owners deserve to hear both sides, and I hope to create a place for honest discussion.

Is spaying & neutering the healthiest choice for dogs?

Potential health benefits to spaying/neutering a dog

Most veterinarians in the United States will advocate early spaying and neutering for all dogs. This is for population control and potential health benefits. Plus, let’s face it, spayed/neutered pets are often easier to live with than intact pets.

Potential health benefits of spaying:

A spay surgery includes removing the female’s uterus and ovaries. Over the years, my dogs’ vets have always told me one of the health benefits of spaying includes reducing the dog’s risk of developing breast cancer.

This is because the spay surgery stops the dog from producing estrogen, and without estrogen, her risk of breast cancer decreases, according to Ted Kerasote in the book “Pukka’s Promise: The Quest for Longer-Lived Dogs.” Breast cancer is the most common type of cancer in intact female dogs, and many vets advocate spaying the dog before her first heat cycle – as young as four months old.

A second health benefit to the spay surgery includes eliminating the dog’s risk of ovarian cancer, since she will have no ovaries. Finally, without her uterus, she has no risk of developing pyometra, which is an infection of the uterus and occasionally fatal, wrote Kerasote in “Pukka’s Promise.”

Potential health benefits of neutering:

As always, the males are a little less complex:

Remove the balls and you eliminate the risk of testicular cancer.

But what is a dog’s risk of developing these diseases in the first place?

It depends on the dog!

There are all sorts of factors that could play a role in a dog’s chances of developing mammary, ovarian or testicular cancer. We have to consider, if possible, the dog’s breed, genetics, family history, age, weight, diet, general health, etc.

Overall, an intact female dog has a 3.4 percent chance of developing breast cancer in her lifetime, wrote Kerasote. If she is spayed before her first heat cycle, her risk drops to 0.5 percent.

Is that enough to justify a spay surgery?

I don’t think so, but that’s up to each dog owner to decide. Plus, you have to consider your dog’s breed and other factors.

A Swedish study listed springer spaniels, Dobermans and boxers as the three breeds with the highest risk for breast cancer out of 51 breeds, according to Kerasote.

And what about the risk of ovarian cancer?

Should I have my dog spayed?

Ovarian tumors are uncommon in dogs, according to Dr. Jeff Werber, a Los Angeles veterinarian. They usually occur in older dogs and generally don’t cause symptoms. However, he still recommends spaying and neutering pets for “overall health, well-being” and medical benefits.

Werber said some reports suggest an increased risk of ovarian cancer for breeds such as Boston terriers and German shepherds. He said the cure rate for malignant ovarian tumors is about 50 percent.

A dog’s breed is also a factor when you consider her risk of pyometra, according to Kerasote. While about half of intact Bernese mountain dogs and Rottweilers will have pyometra at some point, this is only true for 10 percent of beagles. At the same time, a Bernese mountain dog has a very low risk of developing breast cancer in her lifetime.

Do you see how it gets complicated? The best choice for one dog will not necessarily be the best choice for all dogs. And, there’s a lot we don’t know about cancer.

How about the males?

Overall, an intact male dog’s chance of developing testicular cancer is 0.09 percent, Kerasote wrote. Survival rates with early detection are between 90 and 100 percent.

The cause of testicular tumors in dogs is unknown, according to Werber.

“Dogs with undescended testicles are 13 times more likely to develop cancer in the undescended testicle than dogs with normal testicles,” he said. This is believed to be due to the increased body temperature, and no other risk factors have been identified.

As for prostate cancer, some vets will say neutering prevents it, but according to Kerasote, it doesn’t. Newer research says prostate cancer is actually more common in neutered dogs.

Is spaying/neutering the healthiest choice for my dog?

So what are the potential health risks to spaying and neutering?

Again, it really depends on the unique dog and his or her personal risk for certain diseases.

Other cancers, joint issues and more

Some recent studies have shown that spayed and neutered large-breed dogs are more likely to develop bone cancer, according to Werber. This indicates that sex hormones may help prevent bone cancer later in life, and many vets are now recommending waiting to spay and neuter larger breeds until the dogs are a year old.

Some studies say spayed and neutered dogs are more likely to develop hip dysplasia, more likely to tear their ACLs and more likely to have adverse reactions to vaccines, according to Kerasote. Also, if neutered dogs develop symptoms of Alzheimer’s, their symptoms are more likely to progress more rapidly.

According to Kerasote, once dogs are spayed or neutered, their risk of bladder cancer goes up. Spayed females are more likely than intact females to have urinary incontinence. They are also more likely to be prone to obesity.

Werber also said a minor disadvantage to spaying and neutering is that altered dogs do tend to gain weight if no changes are made to their diet. Of course, this can be prevented with a managed diet and exercise plan.

Is neutering the healthiest choice for my dog?

In a study on golden retrievers, males neutered before 12 months were twice as likely to get hip dysplasia and three times as likely to get lymphosarcoma, wrote Dr. Patricia McConnell on her blog The Other End of the Leash. The study also found that females spayed after 12 months were four times more likely to get cancer of the blood vessels than intact females or early-spayed females.

You can read the golden retriever study here [1]. It analyzed five diseases and found that disease rates were significantly increased when neutering or spaying was performed, regardless of age.

McConnell also referenced a 2009 study of female Rottweilers that found dogs spayed after age 6 were 4.6 times more likely to live to age 13 than those spayed at a younger age.

“One doesn’t need to be a veterinarian or a physiologist to suspect that removing hormone-producing organs has a profound effect on a body’s physiology, beyond that of eliminating the potential of reproduction,” McConnell wrote.

Estrogens affect the urinary tract, heart, blood vessels, bones, breasts, skin, hair, mucous membranes, pelvic muscles and the brain, she wrote. Androgens produced in the testes play a role in muscle and skeletal development.

Why the hostility?

Sadly, I know I can’t write about this topic without being “attacked.” For me, it’s important to write about this topic regardless of how the overall pet community responds.

While I care about population control and finding homes for every single dog and cat, I also care very much about the health and longevity of my personal animals.

I’d really like to see people get past the idea that all pet owners who choose not to spay/neuter are automatically “irresponsible.”

I follow the blog Some Thoughts About Dogs, which is written by Tegan Whalan. She is a border terrier breeder in Australia and wrote a post called The Sin of Breeding Dogs. Not surprisingly, she’s been unfairly criticized just for being a breeder.

This is a quote from her post:

“No, I don’t think testicles and ovaries define responsible pet ownership. Responsible pet owners keep their animals contained to their property, ethically treat all medical problems, and only breed healthy dogs that are good representatives of their breed.”

That’s how I see it as well.

I do understand it’s difficult to see past what is right in front of us. I’ve spent a lot of time volunteering with shelters and rescue groups too, and it’s hard to see all those homeless dogs.

But, there is no connection between my dog and what happens to the millions of impounded dogs and cats. They are two separate things. Whether my dog has his balls or not, he’s not going to be mating because I will keep him contained. (Ace was neutered years ago. My pup Remy is not yet neutered.)

Is spaying/neutering the healthiest choice for my dog?

Alternatives to spaying and neutering

I’m not advocating against spaying and neutering, but there are certainly alternatives to consider.

Education on behavior modification

For most of us, spaying and neutering is probably still the best choice considering “fixed” animals are easier to live with (although not always). Most people don’t want to deal with a dog’s heat cycles, marking, etc. But really, are these “issues” all that hard to handle?

There are plenty of dog owners who keep their dogs intact, and dogs and humans manage to co-exist just fine. The dogs don’t mark in the house. No dogs get “knocked up” unless planned. Fights between dogs are not any more common than they are between dogs in any other household, etc.

Maybe some dog owners just need a little more education on how to better manage their intact dogs? I don’t know, what do you think? I’ve never owned an intact dog, so I feel like I could use some education myself.

Less-invasive procedures with the same end result

We spay and neuter for population control, so why do vets overlook the less-invasive options of tubal ligations and vasectomies? These are fairly common procedures in humans. Why can’t we use the same approach with our pets? That way they can’t reproduce, but they’ll still have their beneficial sex hormones.

Doggy birth control?

Obviously this would have it’s own risks as far as hormones, but it’s a viable option.

In September, veterinarians in the United States plan to catch 300 wild female dogs on two isolated Indian reservations and inject them with a birth control vaccine, according to the Associated Press [2]. This will only be a study, but the vaccine has worked on white-tailed deer, wild horses, wallabies and ferrets.

Why wouldn’t it be an option for our pets?

Does your brain hurt yet?

I view spaying and neutering as a personal choice, and what seems like the best choice for my dogs will not necessarily be the right choice for yours. I really don’t know what I’ll do with my future dogs, but all options are worth some serious thought.

I really want to hear what the rest of you think about all this!


1. Gretel Torres de la Riva et al. (2013) “Neutering Dogs: Effects on Joint Disorders and Cancers in Golden Retrievers.” PLoS ONE

2. Susan Manning (2013) “Birth control shots could alter life in poor areas.”

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Andy M, DVM

Sunday 14th of March 2021

The idea that we cut them off as soon as we can find them is felony stupid, though I, like you, understand where the humane societies and rescue societies are coming from.

I'd think maybe a big deposit returnable with proof of sterilization sometime after one year of age might be a solution. Now I'll hear that not everyone can afford the deposit. If this is the case, can they afford to have a pet?

My last 3 male Labs have died virgins with no joint or bone problems.

Like Cathy says, "Judge away,"


Friday 3rd of August 2018

Over 40 years ago, when I adopted my first two dogs, it was pretty common to leave males intact and neuter females after their first heat, which is what I did. I did not want puppies, and I got her through that first year without any significant problem. I was told when I had the female spayed that she would get fat-she didn't, and she lived to be 17. The male, who was an adult when I adopted him, died of cancer, but I have no idea how old he was. I read Ted Kerasote's books, and I realized that if I wanted to wait until what I thought was a reasonable age to neuter my pet, I would have to purchase the dog from a breeder, which I had never done. I don't know if the rescue groups care, because clearly they are very successful at finding homes for pets, but their extremely early neutering policy will, I think, put off more people as time goes on.

Lindsay Stordahl

Friday 3rd of August 2018

Yes, I think more and more people are understanding the benefits of waiting to spay/neuter until the pup is older. Our vet encouraged us to wait with our weim and to consider not neutering him at all.


Sunday 12th of March 2017

I'm having a difficult time with my two male dogs max (shepherd/beagle)and yogi(chow/shiba inu). They used to be best friends until yogi (chow) reached puberty. Now all they do is fight. These are really bad fights. Max is a roamer and was hit about a year ago and had a hip replacement so when they fight he gets hurt the worst. After reading this and many other articles I'm on the fence about neutering... any advice or suggestions would be appreciated.


Tuesday 20th of December 2016

I knew i was on to something here. My wife thought i was nuts to think that spaying our female didnt sit right with me. Because i thought it was unnatural. I want her body to react normaly as it should.


Thursday 3rd of November 2016

I've been on both sides of the road. We had a begal leave us at 8 due to ovarian cancer. We never got her fixed because my parents were planning on breeding her. Looking back, we never had problems with her heats or aggression, or even random dogs coming to get some (she was outside in a dog run). We also had a dog of 13 that we got spayed when she was about 2 or 3 that got cancer in her lymph nodes. Could it have been prevented by having her ovaries? I dunno.

It's hard making those decisions. On one hand, I want to help cut down on stays, but the problem is already here. Clipping Fido's balls may fix things if he gets out and runs away, but if your dog is well controlled like our begal was, then it's not really an issue.

In my lap right now sleeps my new rescued Chihuahua. She was found wandering the streets. She's got clear signs of having a litter and is not fixed. Were those puppies bred, or were they street puppies? And even though we plan to get her fixed, will that really prevent the stray population from growing? probably not.

On the flip side, I live in an area that we consider an animal dump. People dump cats they don't want in a field and the cat is most likely not fixed. We ended up befriending one of these stays and took her to get fixed. Unfortunately we had to move to a different location and the cat refused to come with us but her being fixed DOES help the stray population, even just a little bit. It's one of those terrible paradoxes.

Long story short, there are health risks on both sides. The Chihuahua will be getting fixed, not because I don't want to deal with heats but because in our past, the dogs that are fixed live longer than the dogs that aren't.