Before you bring home a new puppy, you have to do your research. Make sure you’re choosing the right breed for your lifestyle. Think about how you’re going to train him. Find a reputable veterinarian in your area and schedule your new puppy visits.
Once your new puppy is settled in at home, it’s time to start thinking ahead. Veterinarians have traditionally recommended that puppies be spayed or neutered no later than six months of age, so you may have already made an appointment with a local clinic. But is it too soon?
Veterinarian recommendations are changing when it comes to the proper time to spay and neuter pets. In this article, we’ll explore the pros and cons of having your dog fixed and what the experts say about the right time to do it.
Why Should You Spay or Neuter Your Dog?
When you bring a new pet into your life, it becomes your responsibility. In addition to feeding, housing, and providing veterinary care for your new pet, you’re also responsible for its behavior.
Too many irresponsible pet parents find themselves saddled with unplanned litters of puppies and kittens that end up in shelters or find their way into the homes of other irresponsible owners who will continue to breed them. Having your dog spayed or neutered is the best way to do your part in controlling the pet population (as Bob Barker would say).
Here are the potential benefits of getting your dog fixed:
- No unplanned pregnancies or the responsibilities that come with them
- Spayed females are unable to develop uterine, ovarian, or cervical cancers
- Spaying may reduce risk of breast cancer in female dogs
- Neutering male dogs prevents testicular cancer
- Neutered male dogs may have a lower risk for prostate problems
- Altered pets may be less vocal, less aggressive, and have a lower desire to mark
And now, some of the potential downsides:
- While spay/neuter surgery is very safe, there’s always a potential for complications
- Some pets gain weight following a spay/neuter procedure
- Pets altered before sexual maturity may have a higher risk of orthopedic problems
What’s the Right Age?
Traditionally, veterinarians have recommended having pets spayed or neutered in their first year, in many cases before the age of six months. In female pets, some have recommended it before she goes into her first heat cycle. Depending on the pet, this can happen well before 6 months of age.
According to the experts at the American Animal Hospital Association (AAHA), small-breed dogs weighing less than 45 pounds at maturity should be neutered at six months of age or spayed prior to their first heat, around five to six months. Large-breed dogs weighing more than 45 pounds at maturity should be neutered after growth stops, usually between 9 and 15 months.
Early spaying and neutering were long thought to help reduce incidences of endocrine disorders, behavioral problems, and certain types of cancer in pets. A 2013 study conducted by the University of California Davis, however, turned the veterinary world on its head.
The Study That Changed It All
This study, conducted specifically on Golden Retrievers, examined the variables of age and gender at the time of neutering (versus leaving the dog intact) on various diseases. Because cancer and joint disorders are so common in Golden Retrievers, that was the breed selected for the study. The study involved 759 client-owned male and female dogs, both intact and altered, between 1 and 8 years old.
The dogs participating in the study were classified as intact (not neutered or spayed), neutered early (before 12 months), or neutered late (at or after 12 months).
Here are some of the results:
- 10% of early-neutered males were diagnosed with hip dysplasia (HP)
- Twice as many early-neutered males had HD as intact males
- No cases of cranial cruciate ligament tear (CCL) were diagnosed in intact dogs
- 5% of early-neutered males and 8% of early-neutered females had CCL
- Nearly 10% of early-neutered males were diagnosed with lymphosarcoma (LSA)
- The incidence of hemangiosarcoma (HAS) was four times higher in late-neutered females than in intact and early-neutered females
- There were no cases of mast cell tumor (MCT) in intact females and 6% in late-neutered females
While this was one of the first studies which suggested it may not always be beneficial to alter dogs early, it wasn’t the only one. A 2020 article published in the Frontiers of Veterinary Science analyzed previous research to provide veterinary professionals with guidance on the matter.
Some of the findings mentioned in the article include:
- Large breeds neutered before one year of age experienced a 2-to-4 times higher risk for joint disorders than intact dogs.
- Small breeds seemed to have no increased risk of joint disorders associated with neutering.
- Neutering may be associated with a 3-fold increase in excessive tibial plateau angle, a risk factor for cranial cruciate ligament tears and ruptures.
- Certain types of cancer (like lymphoma, hemangiosarcoma, and mast cell tumors) are more likely to be found in neutered than intact dogs.
While the results of these studies provide key insights, the authors of the 2020 article suggest that the studies don’t offer much in the way of clinically useful information. They also don’t provide any guidelines regarding the specific breeds or diseases studied.
What Are Veterinarians Saying Now?
Though it’s difficult to draw definitive conclusions from a handful of scientific studies, recent research seems to suggest that spraying and neutering puppies can affect their growth and development.
Spaying or neutering a puppy earlier in life, removing the reproductive hormones that help regulate the process of development, could increase the overall period of growth. Experts already know that excessive growth in large-breed puppies increases the risk for orthopedic problems in adulthood, so perhaps the same theory applies here. At least in the case of large-breed puppies and breeds already predisposed to orthopedic issues.
The complicating factor is that, by waiting to spay or neuter a puppy to protect its orthopedic health, you may put it at risk for certain types of cancer.
Spaying female pets before their first heat essentially eliminates the risk for mammary cancer. Female dogs seem to receive this benefit if they’re spayed up to the age of two, though the incidence increases with each estrus cycle. Waiting to spay a female dog also increases the risk for unwanted pregnancy.
When you choose to spay or neuter your dog could even have an impact on its bodyweight. A lifetime study of Golden Retrievers published in PLOS One in 2019 revealed that dogs who were spayed and neutered were more likely to be overweight or obese.
As your dog’s caretaker, it’s ultimately your decision whether you have your dog spayed or neutered. It’s also your right to decide when. Before you make this decision, however, it’s wise to consult your vet.
Your veterinarian has the training and experience to make educated recommendations about your dog’s care. But you’re not obligated to follow them blindly. If your vet unilaterally recommends alteration for dogs under 1 year of age, push back and ask questions. Does that recommendation apply to large breeds as well as small breeds? What about breeds prone to orthopedic issues?
If your vet doesn’t seem to be up to date on the information discovered in some of the studied mentioned above, you may want to get a second opinion.
At this point, no definitive conclusions have been reached regarding the impact of early or late spaying and neutering of dogs. The best thing you can do is educate yourself about the options and include your veterinarian in the conversation as you make your decision.
Frequently Asked Questions
- What’s the difference between spaying and neutering a dog? – Neutering is a procedure performed on male dogs and spaying on female dogs. When a male dog is neutered, it involves removing the testicles to render the dog sterile. For female dogs, the dog’s uterus and ovaries are surgically removed.
- What age should a dog be spayed or neutered? – While vets previously advocated for spaying and neutering by 6 months of age, new evidence suggests it may be better to wait 6 months or longer. The benefits of delayed spay and neuter may be more pronounced in larger breeds than in small dogs.
- Is it more expensive to spay or neuter a dog? – Though some clinics will charge the same amount for either, it is generally more expensive to spay a female dog than to neuter a male dog. Neutering is a fairly simple procedure while spaying is a more invasive surgery.
- How long does spay and neuter surgery take? – In most cases, spay or neuter surgery only takes between 30 and 60 minutes. This generally includes the time needed for preparation and anesthesia. The procedure may take longer and could require more than one surgeon for older or larger dogs than for puppies.
Double-certified Pet Food Nutrition Specialist & Expert Pet Writer
Kate Barrington holds a Bachelor’s degree in English and is the published author of several self-help books and nutrition guides. Also an avid dog lover and adoring owner of three cats, Kate’s love for animals has led her to a successful career as a freelance writer specializing in pet care and nutrition. Kate holds a certificate in fitness nutrition and enjoys writing about health and wellness trends — she also enjoys crafting original recipes. In addition to her work as a ghostwriter and author, Kate is also a blogger for a number of organic and natural food companies as well as a columnist for several pet magazines.