When Should I Spay or Neuter my Dog??

There is no easy answer!

I know that’s not what you all wanted to hear! But its very nuanced and dog and family dependent.

“Decisions on whether and when to neuter a specific dog are complicated and reflect a consideration of the dog's breed, health status, and living situation, as well as available information pertaining to risks for these joint disorders and cancers. These varied results highlight the complex effects of neutering and the age at which it is conducted.” - UC Davis School of Veterinary Medicine

Why is spaying/neutering important?

There’s no doubt that we have too many pets that spend their life in shelters, rescues, and bouncing around foster homes. Spaying and neutering pets can decrease the incidence of unplanned pregnancies in our companion animals so they don’t have to live their life in a shelter or sadly get euthanized when there is no room (a horrible reality in some areas).

There are also cancers that develop when dogs are left intact, such as mammary and testicular cancer. Spaying can reduce the risk of mammary cancer by a lot!

“According to the American College of Veterinary Surgeons, the risk of your dog getting mammary cancer is: 0.5% risk for female dogs spayed before their first heat cycle. 8% risk for female dogs spayed after their first heat. 26% risk for female dogs spayed after their second heat.”

An infection of the uterus, pyometra, is an emergency situation that ultimately results in spaying the animal (along with antibiotics, fluids, hospital stay etc). This infection can occur if females aren’t spayed.

But now studies have shown that delaying spaying and neutering can help other body systems, such as joints, urinary incontinence, and reduce some cancers. The majority of cases I see on a daily basis are arthritic, painful dogs that have a poor quality of life. Could delaying spay/neuter slow down that progression??

All of this is very nuanced, and a good discussion with your vet is warranted. Lets look at a recent research paper that UC Davis came out with, and what it all means for your dog.

UC Davis School of Veterinary Medicine published a paper and chart on ideal times to spay and neuter dogs. This is a lot to take in!

Scroll down to the bottom of this blog to get the short answer on what I tell my clients.

In this most recent paper, they focused on 5 breeds specifically. There is a lot of information in the article, so I urge you to read it if you have one of these breeds:

German Short/Wirehaired Pointer, Mastiff, Newfoundland, Rhodesian Ridgeback, Siberian Husky.

It covers cancers and joint disorders but I will just talk about joint issues since that is my focus as a clinician! I’ll pick out a few key points:

German Short/Wirehaired Pointer - “In intact male and female dogs, the occurrence of a joint disorder was 3% and 2%, respectively. CCL was slightly elevated for male dogs neutered before 1 year, and the occurrence of joint disorders was highly elevated for female breeds neutered before 6 months, with 38% having at least one joint disorder.”

Mastiff - “Intact male and female dogs had a 6% and 9% risk of at least one joint disorder, respectively. Neutering male dogs before 2 years resulted in a significantly elevated risk for a joint disorder, mainly due to CCL; neutering before 1 year was a 21% risk, and neutering at 1 year of age was a 15% risk. Although not significant, female dogs neutered before 1 year had a 20% risk of a joint disorder.”

Newfoundland - “Intact male and female dogs had 10% and 7% rates of having at least one joint disorder, respectively. Males' rates after neutering were not significantly elevated, but females' rates for having a joint disorder were significantly elevated: 39% were affected when neutered in the 1st year.”

Rhodesian Ridgebacks - There was no mention of joint issues in the discussion for this breed. “Intact male and female dogs had 14% and 13% risk for at least one cancer, respectively. Neutering female dogs before 6 months provided the only significant increase in cancers, with a 25% rate of MCT compared with the 3% rate in intact female dogs.”

Siberian Husky - “Intact male and female dogs both had a 2% risk for joint disorders. Although neutering resulted in no significant risks for joint disorders over that of intact dogs, female dogs neutered before 1 year had a 12% chance of CCL, which would perhaps be significant with a larger dataset.”

What is my “short” answer as a jumping off point for further discussion with my clients?

I like to wait until about age 2 years old for both males and females. Larger sized dogs have more joint issues in general, so I urge clients with bigger dogs to wait 2 years. If that is not in line with the family (heat cycles & diapers are too much, day care or boarding requires spay/neuter etc) then I urge clients to wait at least until after the females first heat cycle, and for males at least 1 of age.

The article also suggested to leave a few female breeds intact, but I always discuss with clients the risk of Pyometra and Mammary Cancer.

There are ovary sparing spays, meaning the ovaries stay within the female, but the uterus and cervix is removed. This is less practiced (and not taught as much in vet school!) so there may not be a vet in your area that provides this surgery.

I hope this helps in guiding you to understand when to spay and neuter your pet! As always, your veterinarian is the best person to make this decision with.