When to Spay or Neuter Your Dog

Medical articles
french bulldog puppy in a cone after getting neutered

It’s no secret that the United States has a huge homeless pet problem. So much so that 3.1 million dogs go through the shelter system every year. There’s no doubt about it, spaying and neutering your dog is the best way to decrease the number of homeless pets, but many dog parents wonder when to neuter or spay a dog. So, we’re here to give you some general guidelines on the best age to have a dog spayed or neutered. 

Benefits of Spaying and Neutering Your Dog 

As we’ve briefly touched on, spaying and neutering your dog is the best way to decrease unwanted litters, and reducing the number of unwanted litters is the most effective strategy to minimize the homeless pet population. 

Aside from that, spaying and neutering your dog can actually reduce the risk for many cancers and diseases related to the reproductive tract. Ovarian and testicular cancer and uterine infections become impossible, and mammary cancer and prostate problems become greatly reduced with spaying and neutering. These changes occur because the reproductive organs are removed (ovaries and testicles) or because the reproductive hormones have less influence on other organs (mammary glands and prostate). 

Spaying also eliminates heat behaviors in your female, including bleeding, frequent urinating and the incessant licking. Neutering can reduce testosterone levels in male dogs, which can lead to a decrease in aggression, roaming, and marking behaviors. 

The behavior changes you may see are due to removing the reproductive hormones that are driving those behaviors. The reduction in testosterone after neutering, in particular, can have major impact on behavior. 

Age Considerations for Neutering Male Dogs 

For many years, the conventional wisdom was that all dogs should be neutered at six months of age. New research suggests that waiting to neuter your dog until they are older, such as 12 to 18 months, may help prevent joint injuries and some types of cancer, such as testicular cancer and osteosarcoma. This is because neutering too early can interfere with the normal development of bones and muscles.   

Factors Affecting the Ideal Age of Neutering 

All systems in a dog’s body are connected, including the reproductive system and the joints. Reproductive hormones play a part in a dog’s growth and development. As a result, neutering some dog breeds before they are fully grown can increase their risk for things like hip dysplasia, elbow dysplasia, and even cranial cruciate injuries in the knee. In some breeds, neutering before one year of age can also increase a dog’s risk of developing cancers like lymphoma, osteosarcoma, and mast cell tumors. 

Since we also know that not neutering has its fair share of health risks, it can be a delicate balance to determine when to neuter a dog so that you’re achieving the best of both worlds. Much of this balancing act has to do with when a dog reaches sexual maturity. In the perfect world, you would neuter a dog just before they reach sexual maturity to prevent the myriad of issues that reproductive hormones and organs can bring about. But you also want to give your dog as much time as possible to grow and develop. 

With this in mind, here are the general recommendations for when to neuter a dog. 

When to Neuter Smaller Breeds 

Smaller dog breeds under 40 pounds tend to suffer from fewer orthopedic issues than their larger counterparts. This is partially due to genetics and partially due to less weight stress on the joints. So, for smaller dogs, neutering between 6-12 months of age is generally recommended.  

When to Neuter Larger Breeds 

Dogs that are going to be larger than 40 pounds should be given a little bit more time to grow and mature, so waiting until these dogs are 9-18 months old before neutering is usually best.  

Of course, there are always exceptions to the rule. For example, a veterinarian may recommend neutering a large breed dog earlier than 9 months old if the dog is showing signs of aggression or is at risk of developing testicular cancer. It is important to talk to your veterinarian about the best time to neuter your large breed dog based on their individual needs. 

Age Considerations for Spaying Female Dogs 

Some female dogs, especially those coming from shelters, are spayed early, sometimes as early as 3 months. This is to prevent unwanted litters, but it's important to note that spaying puppies at 3 months is not always in their best health interests. 

Factors Affecting the Ideal Age of Spaying 

Female dogs have the same relationship between reproductive hormones and growth and development as male dogs, but they also have heat cycles. Many owners want to avoid heat cycles, which can be messy, annoying, and uncomfortable. This is why spaying at six months of age became popular, as it is typically before the first heat cycle. However, female dogs, especially larger breeds, can benefit from more time to grow and develop before being spayed. This helps to prevent orthopedic problems and some types of cancer. 

Determining the best time to spay a female dog can be challenging, as it is a balance between sexual maturity and growth.  

Spaying Smaller Breeds 

No matter the size, puppies should wait until at least six months of age before spaying. This just helps their body handle the anesthesia and surgery with less stress. However, smaller breeds also reach sexual maturity at a younger age, so sticking with that 6–12-month mark works well for most dogs under 40 pounds. 

Spaying Larger Breeds 

Larger breeds do tend to reach sexual maturity later than smaller breeds, but they don’t wait forever, so work with your vet to decide when to spay your dog so that you’re getting the most out of their growth and development, while avoiding the start of heat cycles. In general, 6-9 months, or later, is best. 

Tailoring the Decision to Each Individual Dog

All of the above are just general guidelines. What's best for your individual dog may vary. That's why it's important to consider your dog's unique needs when making the decision about when to spay or neuter them.  Here are some additional factors that you and your veterinarian may want to consider: 

  • Your dog's breed: Some breeds of dogs are more prone to certain health conditions, such as hip dysplasia or elbow dysplasia. Neutering or spaying too early can increase the risk of developing these conditions in some breeds. 

  • Your dog's projected size: Larger breed dogs tend to mature more slowly than smaller breed dogs.  

  • Your dog's potential health concerns: If your dog has any underlying health conditions, such as cryptorchidism (retained testicle) or pyometra (a uterine infection), your veterinarian may recommend spaying or neutering them sooner. 

  • Your dog's lifestyle: If your dog is an active working dog or a show dog, their reproductive hormones may play a role in their performance. Talk to your veterinarian about whether to delay spaying or neutering your dog until after they have retired from working or showing. 

It is important to remember that there is no one-size-fits-all answer to the question of when to spay or neuter a dog. The best time to do so will vary depending on the individual dog's needs. Talk to your veterinarian to determine the best timing for your dog. 

Paying for Spaying or Neutering 

You’ll also want to take other things into consideration. For some this may be finances, as the cost of neutering a dog and the cost to spay a dog can be significant. The logistics of recovery, and even the time of year may also play a role. Again, consult with your veterinarian to determine what’s best for your dog. 

A good dog wellness plan, an optional add-on to pet insurance, can help you budget for those extra expenses. While pet insurance covers unexpected accidents and illnesses, a wellness plan reimburses you for expenses like spaying and neutering. Pet insurance and wellness plans help you turn unexpected expenses into predictable costs so you never have to decide if you can afford care your pet really needs! 

When to Spay or Neuter Your Dog is an Important Choice 

There’s no doubt about it, spaying and neutering dogs is the single best way to prevent unwanted litters, which in turn, helps decrease the unwanted or homeless pet population. Spaying and neutering also help decrease or eliminate many reproductive related health and behavior problems. However, doing it too soon may create some problems of its own. So, be sure to discuss your dog’s specific needs with your veterinarian to determine the best age to spay or neuter your dog. Your pup is a precious gift, and they deserve the best that life has to offer. By carefully considering the timing of spaying or neutering your dog, you're giving them the gift of a long, healthy, and happy life.