Should You Spay/Neuter Your Giant Breed Dog? What the Latest Research Says

There was a time when the advice was simple: spay or neuter your dog around six months of age. Period. End of story.

But like most things in the world of veterinary care, the more we learn, the more we realize it’s not always that simple—especially when it comes to giant breeds.

The decision to spay or neuter is still incredibly important. But the timing of that decision? It might matter even more than we once thought.

The Traditional Approach (and Why It’s Changing)

Historically, most dogs were fixed around 6 months old. The push came from well-meaning efforts to reduce overpopulation and avoid hormone-related behaviors like marking, roaming, or aggression.

But newer research has raised important questions—particularly around how early sterilization affects growth, joint development, and long-term disease risk in large and giant breed dogs.

Why? Because these dogs grow fast and they grow big. Altering their hormone levels before growth plates have closed may increase the risk of orthopedic issues down the road.

What the Science Says Now

Multiple studies now suggest that delaying spay/neuter in large and giant breed dogs can help reduce the risk of:

• Hip dysplasia
• Cruciate ligament tears (CCL injuries)
• Certain cancers, including osteosarcoma and hemangiosarcoma

One landmark study from UC Davis Veterinary School looked at Golden Retrievers and found significantly higher rates of joint disorders and cancers in dogs that were altered before 1 year of age.

While every breed is different, the trend is clear: hormones play a key role in how bones, joints, and tissues mature.

Pros and Cons of Spay/Neuter for Giant Breeds

There are still very valid reasons to consider sterilization—but understanding the trade-offs helps you make a more informed decision.

Pros:

• Prevents unwanted litters
• Reduces risk of mammary or testicular tumors
• Can curb some hormone-driven behaviors like mounting, marking, or roaming
• May be required by breeders, shelters, or local laws

Cons:

• Early sterilization may increase orthopedic risk (hip, knee, spine)
• Potential for certain cancers to develop based on age/sex
• Hormonal changes can affect growth rate, metabolism, and behavior

So, What Should You Do?

There’s no one-size-fits-all answer here. But if you’re parenting a giant breed dog, these are the factors to consider:

• Age & breed: Some breeds mature slower and benefit from delayed alteration.
• Sex: Risks and timing recommendations differ between males and females.
• Lifestyle: Is your dog around intact animals? Are you able to safely manage them if left unaltered for longer?
• Veterinary input: Talk to a vet familiar with giant breeds or orthopedic health.
• Breeder recommendations: Reputable breeders often have guidelines based on decades of breed-specific experience.

Questions to Ask Your Vet

When you talk to your vet, ask:

• When do growth plates typically close for my dog’s breed?
• Are there health risks to delaying spay/neuter in my case?
• What are the behavioral implications of waiting vs proceeding early?
• Can we do hormonal or orthopedic screening first?

Giant Dogs Deserve Giant Conversations

Spaying and neutering are still important tools in responsible pet ownership. But for giant breeds, it’s okay to pause and ask more questions.

What matters most is that you feel informed, supported, and empowered to do what’s right for your dog.

Because when it comes to these big, beautiful animals, there are no shortcuts—just thoughtful care, one decision at a time.