Best Time to Neuter/Spay

What Is the Best Age to Spay or Neuter Your Dog or Cat?


by Lorie Huston, DVM on October 14, 2013

This is a question I hear frequently from pet owners. When should I spay or neuter my pet? So, let’s talk a bit about that.
What is the best age to spay or neuter your dog or cat?

Defining Spay and Neuter

Let’s start with some definitions. The word spay refers to altering a female through removal of part or all of the reproductive tract. The term neuter, though it can refer to altering of either a male or female, is typically reserved (at least in a hospital setting) to the altering of a male through removal of the testicles.

What Is the Best Age to Spay or Neuter?

Now on to the real question: What is the best age to spay or neuter your dog or cat?

Let’s look at some statistics:

  • 79% of pet owners don’t know when to spay or neuter their pet. This uncertainty about the appropriate age is one of the biggest barriers to spay/neuter.
  • 13-19% of pet owners have allowed their pets to have at least one litter. Of those, roughly 50% were the result of an accidental unplanned mating.
  • Although there are variations, cats can have their first heat as early as 4 months old. Dogs can have their first heat as early as 5 to 6 months old. An animal that is in heat can become pregnant!
  • About 1/2 of all pet owners don’t know whether their pet would benefit from having a litter before spaying or believe (mistakenly!) that she would benefit.

Source: WhenToSpay.Org

Early age spaying and neutering is beneficial in several ways.

  • Spaying or neutering is more easily performed at a young age, with less accumulated fat to complicate the procedure and less blood loss during the procedure.
  • Early age spaying and neutering is less stressful for your pet.
  • Young pets tend to recover more quickly.
  • The procedure is likely to be much less expensive for you when performed at an early age.
  • Avoiding the first heat cycle in female pets removes the potential for unplanned pregnancies, aiding in reducing the unwanted pet population.
  • Early age spaying has the following benefits: it virtually eliminates the risk of breast tumors (50% of which are malignant), eliminates the risk of cystic endometrial hyperplasia and pyometra, eliminates the risk of uterine and ovarian cancer, eliminates behaviors associated with the heat cycle, and decreases spraying behavior.
  • Early age neutering benefits males by: eliminating the risk of testicular cancer, decreasing prostate disease (such as benign prostatic hyperplasia and prostatitis), decreasing fighting, decreasing roaming, decreasing spraying/marking behavior, and eliminating the odor of tomcat urine.

What age is “early age”? For animals in shelter situations, two months of age and/or two pounds in weight are the accepted guidelines. This has the advantage of allowing the pet to be spayed or neutered prior to adoption, eliminating the possibility that pet owners will not follow through on having the procedure performed.

For owned animals, spaying or neutering 2-3 weeks after the final vaccination is typically a good age. At our hospital, we generally recommend spaying and neutering at 4 months of age for the majority of animals.

Though spay/neuter is often recommended between 6-9 months of age, the fact is that this recommendation is not based on any evidence in the scientific literature. Truthfully, we don’t know the ideal age. However, we do know that early age spay/neuter is safe for your pet.

The Risks of Early Age Spay/Neuter

There have been some studies done that have indicated that certain types of orthopedic disease, urinary tract disease, and some types of cancer may be more common in dogs spayed or neutered at an early age. This research, however, is not perfectly definitive. While we should keep this information in mind, we do know that sterilized pets live longer than intact pets overall.

Here are the statistics (based on the 2013 Banfield State of Pet Health Report):

  • Neutered male cats live 62% longer than unneutered males.
  • Neutered male dogs live 18% longer than unneutered males.
  • Spayed female cats live 39% longer than unspayed females.
  • Spayed female dogs live 23% longer than unspayed females.

There may be specific pets, especially in cases where the pet’s ancestral history indicates a predisposition for these higher risk diseases, when postponing a spay or neuter may be desirable though. This is a choice that should be made based on evaluation of all known risk factors weighed against the potential benefits.

Other Considerations

There are a few other considerations that may come into play when determining the best age to spay or neuter an individual dog or cat.

  • The appearance of the breed in question is an important consideration. Some breeds may not acquire the mature characteristics of the breed if neutered or spayed at an early age.
  • We need to keep the purpose of the pet in mind. Sporting dog breeds and show animals, for instance, may be better spayed or neutered at a more mature age.
  • The pedigree, if known, should be examined for risk factors, such as the incidence of mammary tumors, osteosarcoma, hemangiosarcoma, and other types of diseases that may be impacted positively or negatively by the pet’s age at the time of surgery.
  • Some pet owners are better able to control intact animals than others. Inexperienced pet owners should consider spaying or neutering sooner rather than later.
  • If there are other pets in the household, their age, breed, sex, and reproductive status should be considered.
  • In household with young children, spaying or neutering early should be strongly encouraged. Unaltered dogs are, at least statistically, more likely to bite than altered animals.

The bottom line is that we still have a lot unanswered questions about the best age for spaying or neutering a pet dog or cat. There is no right or wrong answer that is all-encompassing. Each pet and its situation is unique and should be evaluated as such. In most cases, early age spay or neuter is a good choice. However, there may be some cases where the procedure is best postponed to a more mature age. Your veterinarian can help you weigh all the factors and make an appropriate decision for your pet.

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About Lorie Huston, DVM Lorie Huston is an accomplished veterinarian, an award winning blogger, a talented author and a certified veterinary journalist. She is available for writing assignments, blogging and social media consultation, and SEO strategy.

This article is posted and shared through the courtesy of the Pet Health Care Gazette