08/28/2026
Big medicine company
🐾 FRIDAY LEARNING SERIES: LET’S TALK ABOUT EARLY SPAY & NEUTER
For years, the standard advice for dogs was simple: spay or neuter at around 6 months of age.
But veterinary research has increasingly shown us that it isn’t quite that simple—particularly when we’re talking about large, athletic, working dogs.
This isn’t an argument against spaying or neutering. There are very real benefits to sterilization, including preventing unwanted litters, eliminating the risk of certain reproductive diseases, and dramatically reducing the risk of mammary tumors when females are spayed before their first heat.
The question is:
Does timing matter?
The answer appears to be yes.
🦴 ORTHOPEDIC HEALTH
S*x hormones play an important role in skeletal development and growth-plate closure. Removing those hormones before a dog has finished growing can alter the way the bones and joints develop.
Research has found associations between early sterilization and increased rates of orthopedic problems including:
• Hip dysplasia
• Elbow dysplasia
• Cranial cruciate ligament (CCL) injuries/ruptures
This is particularly important for larger dogs and dogs expected to participate in athletic activities such as hunting, hunt tests, field trials, agility, or other demanding work.
In one large UC Davis study examining 35 breeds, early neutering was associated with increased joint-disorder risk in several larger breeds. The researchers emphasized that the effects vary considerably by breed and s*x. (Frontiers)
🧬 CANCER RISK
This is where the conversation gets even more complicated.
Some cancers become less likely after sterilization, while research has found that sterilization—particularly at certain ages—may be associated with an increased risk of other cancers in some breeds.
Studies have investigated associations with cancers including:
• Osteosarcoma
• Hemangiosarcoma
• Lymphoma/lymphosarcoma
• Mast cell tumors
These risks are not the same for every breed.
Even AAHA acknowledges that cancer risk can vary by tumor type, breed, s*x, and timing of sterilization. (AAHA)
💧 URINARY INCONTINENCE
Early spaying can also be associated with urinary incontinence in female dogs.
AAHA notes that urethral sphincter mechanism incompetence is more common overall in spayed females, with some studies suggesting the risk is greater when females are spayed before their first heat. (AAHA)
⚖️ WEIGHT & METABOLIC CHANGES
After gonadectomy, dogs can experience changes in metabolism and appetite that make maintaining an appropriate body weight more difficult.
The 2024 WSAVA guidelines note that gonadectomized dogs have a reduced metabolic rate and that weight gain and obesity can become concerns if food intake and activity aren’t adjusted accordingly. (WSAVA)
And for a sporting dog, maintaining a healthy body condition isn’t just about appearance—it directly affects mobility, athletic performance, and joint health.
SO… SHOULD YOU WAIT?
There isn’t one universal answer.
AAHA’s current guidance recognizes that timing should take into account a dog’s projected adult size, breed, s*x, lifestyle, and individual health risks. For large dogs, their guidelines generally recommend waiting until growth is complete or close to complete, rather than automatically sterilizing at six months. (AAHA)
That doesn’t mean every large dog should remain intact for a specific number of years.
It means we should stop treating every dog like the same dog.
A 12-pound companion dog, a 90-pound Chesapeake, and a high-drive field Labrador have very different growth patterns, workloads, and health considerations.
For our sporting and working dogs, we believe it’s worth having a conversation with your veterinarian about WHY you’re sterilizing, WHEN you’re doing it, and what the potential long-term tradeoffs may be.
The goal isn’t simply to prevent reproduction.
The goal is to give our dogs the best chance at a long, healthy, active life. 🐾
📚 SOURCES & FURTHER READING
• American Animal Hospital Association (AAHA) — Canine Life Stage Guidelines & spay/neuter timing
• Hart et al., University of California, Davis — Assisting Decision-Making on Age of Neutering for 35 Breeds of Dogs
• Hart et al. — research examining joint disorders, cancers and neutering in retrievers
• World Small Animal Veterinary Association (WSAVA) — 2024 Guidelines for Control of Reproduction in Dogs and Cats
As always, this is an educational discussion—not a substitute for veterinary advice. Your veterinarian can help you determine the appropriate timing for your individual dog.
👇 What age did you spay or neuter your dog, and did your veterinarian discuss timing based on breed, size and lifestyle?
