Neutering

Neutering (also called spaying in females and castration in males) is one of the most common procedures we carry out but it is important to be fully informed before deciding when to have your pet neutered. In 2024, the World Small Animal Veterinary Association (WSAVA) published updated global guidelines on reproduction control in dogs and cats, moving away from a blanket approach and towards individualised advice based on species, breed, size, lifestyle and the animal's own health history.

We've summarised the key points below, but every animal is different — if you're at all unsure what's right for yours, please get in touch and we'll talk it through with you.

What does neutering involve?

  • Female dogs and cats (spaying): removal of the the ovaries and uterus (ovariohysterectomy), preventing seasons and pregnancy.

  • Male dogs and cats (castration): removal of the testicles, preventing fertility and reducing testosterone-driven behaviours.

  • Both are carried out under general anaesthetic, with pain relief given before, during and after surgery.

What has changed in the guidance?

Historically, blanket early neutering was recommended for most pets. The current WSAVA guidelines take a more individualised view, recognising that:

  • The right age and approach depends heavily on species, breed, size and lifestyle.

  • Responsible, well-supervised pet owners may reasonably choose to keep some dogs entire, particularly certain breeds prone to complications after neutering.

  • Timing can meaningfully affect the balance of health risks and benefits, especially in large and giant breed dogs.

This doesn't mean neutering is no longer recommended — for most pet owners it remains a sensible choice — but the "right" age and decision is now considered on a case-by-case basis rather than a fixed rule for every animal.

Cats

  • Female and male cats of average adult size can be safely neutered from around 4 months of age, without evidence of harm to health, life expectancy or behaviour.

  • Neutering before the first season is particularly effective at reducing the risk of mammary tumours in female cats.

  • Neutering reduces roaming, fighting and urine spraying, especially in males.

  • We recommend around 5-6 months of age in most cases.

Potential downsides to be aware of:

  • Increased risk of weight gain and obesity after neutering — manageable with diet and exercise.

  • Slightly increased risk of certain urinary tract issues.

  • Possible effect on growth plate closure if neutered very young, which is rarely clinically significant in cats.

Dogs

There is no single "correct" age that applies to all dogs. Current guidance suggests that the balance of risks and benefits varies with:

  • Size and breed: for example, larger and giant breeds are more likely to benefit from waiting until they have reached skeletal maturity before neutering, due to a higher risk of joint problems (such as cruciate ligament disease) associated with early neutering in these breeds.

  • Sex: the risks and benefits differ somewhat between males and females.

  • Lifestyle and temperament: working dogs, multi-dog households, and dogs with specific behavioural concerns may all need a different approach.

  • Health history: certain existing conditions may make neutering more or less advisable at a given time.

Potential benefits of neutering:

  • Removes the risk of pregnancy and reduces the risk of certain reproductive diseases, including pyometra (womb infection) in females and testicular disease in males.

  • Can reduce the risk of mammary tumours in females, particularly when performed around the first or second season.

  • May reduce some hormone-driven behaviours, such as roaming, mounting and inter-male aggression, in some dogs.

Potential downsides to be aware of:

  • Neutering at a very young age has been associated with an increased risk of certain joint problems in some breeds, particularly larger dogs.

  • Slightly increased risk of certain cancers and of urinary incontinence in some female dogs, particularly larger breeds neutered early.

  • Possible increase in weight gain, so diet and exercise become more important after the procedure.

  • Behavioural change following neutering can vary between individuals and isn't always predictable.

Our approach

Because the right decision now depends on your individual dog or cat, rather than a fixed age for every pet, we'll always discuss:

  • Your pet's breed, size and health history

  • Your household and lifestyle

  • The timing that best balances the benefits and risks for your specific animal

Still unsure?

If you have any doubt at all about whether, or when, to neuter your pet, please don't hesitate to contact us on 01797 252321. We're always happy to talk through your options and help you make the right decision for your animal.