Have you heard of neutering implants? Maybe you have and you are curious to know more, or maybe you are none the wiser and have come here for the low down on them. Neutering, as we know it in animals, involves the surgical removal of testicles in male animals or the ovaries in female animals. Surgery has always been the primary method used in veterinary medicine. However, vets can use another method as a less invasive alternative. 

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Neutering implants are small capsules inserted under the animal’s skin that release hormones. The effects of the implant mimic those of surgical neutering, however with a catch, they are only temporary. Once the hormones in the implant run out, the effects wear off. They usually last for six to twelve months, depending on the size of the implant. Once the effects wear off, the animal will regain fertility once more. 

This article will delve into the advantages and disadvantages of neutering implants and will discuss their potential place in veterinary medicine. 

Surgical Neutering 

Surgical neutering of animals is widely regarded as the gold standard for animal sterilisation. There are many well-documented health benefits for your pet, let’s discuss these below: 

Prevention of unwanted pregnancies 

Surgical neutering is a surefire way of preventing any unwanted litters. There are many animals in rescue centres that need rehoming, responsible neutering prevents overpopulation and overcrowding in animal shelters and rescue centres. 

Reduced risk of cancers 

For females, neutering can eliminate and/or reduce the risk of ovarian and uterine cancers as well as mammary cancers. In male dogs, neutering reduces the risk of testicular cancer.

Behavioural benefits 

There can be positive changes in behaviour for both female and male animals. Lots of owners will report a reduction in unwanted sexual behaviours such as humping and mounting. It can decrease roaming activities and unwanted vocalisation – calling for a mate. It can also stop some animals from marking territory with urine, which can be a frustrating problem if they decide to do this in our homes! 

Prevention of certain infections 

Neutering in females can prevent a serious infection from occurring in the uterus called a pyometra. 

Reduced injuries from fighting or road traffic accidents

Neutered animals are less likely to get into fights with potential competitors for a mate; likewise, they are less likely to roam and put themselves in danger from traffic.

Reduced Spread of disease 

Neutered animals are less at risk of picking up sexually transmitted diseases. 

Of course, there are potential downsides to neutering as well – although they are less well understood. An overview of the current state of knowledge is outlined in the recent WSAVA guidance.

The low down on neutering implants 

Neutering implants are relatively new compared to the traditional ways of sterilisation. The implant works by being placed under the skin and slowly releasing hormones into the body that mimic surgical neutering. In males, the hormones suppress testosterone production and in females they suppress oestrogen. Implants last a different amount of time depending on their size. 

There are a few potential advantages of neutering implants which we will discuss below:

Less invasive 

The main advantage is that they are much less invasive than traditional surgery. They can be implanted in a conscious animal a lot of the time, which eliminates the anaesthetic risk. Some animals will not tolerate them being implanted when conscious so it is always a good idea to discuss your pet and their temperament with your vet. 

Reversible 

As the implants only last a fixed amount of time, their effects are only ever temporary. This is a big advantage for owners who are unsure about neutering their pets and wish to delay neutering. One of the most common uses of neutering implants is in dogs to trial how they will behave if they are surgically neutered. This is a popular option for owners who want to know if certain behavioural issues (especially anxiety or aggression) will be worsened or improved if their dog has been castrated. If the desired result is not seen, then the advantage is that the effects will reverse in a short period of time, depending on the size of the implant used. 

Cost 

In *some* cases, implants can be a cheaper option than surgery.  It does depend on the size of the animal and how long implants are going to be used for though. 

What are the issues with neutering implants? 

There are quite a few drawbacks to neutering that need to be considered carefully before using them. 

Lack of research 

When compared to traditional surgery techniques for neutering, there is relatively little research on the long-term effects of implants. This means that we may not yet grasp the full impact of the implants on the general health and the behaviour of our pets. 

Temporary Effects

Although listed as an advantage in some instances, the fact that the implants are not permanent can be very disruptive and inconvenient for animals and their owners. The temporary nature means that repeated procedures are required over time to ensure the animal does not become fertile again. This can be distressing for them and can cause them pain and discomfort. It can also become very costly long-term. 

Side Effects 

As with any medication or drug, there are potential side effects. These can be mild and self-limiting or quite serious. Some animals experience swelling at the injection site, changes in appetite and increased aggression or anxiety. They can have adverse reactions to the implant and the site can become infected. 

Availability 

Implants are not readily available in some areas so may prove difficult to get hold of. This can also bump up the cost of things. 

Are neutering implants right for you and your pet? 

The decision of whether neutering implants are right for you and your pet should be made after having a frank chat with your vet. It should be made based on the individual circumstances including the health and temperament of the animal and your financial situation.

The main points up for discussion include: 

Your pet’s age and health status 

Implants are not recommended for use in very young or elderly animals or any animals that have ongoing health issues. The exception is in animals where neutering is required, usually for medical reasons, but they aren’t well enough to undergo an anaesthetic – for example, dogs with severe heart disease.

The duration of sterilisation required 

If you want your pet to be permanently sterile, surgical neutering will always be the best option. 

Finances 

The potential costs of neutering implants compared to a one off surgery need to be considered. 

Behavioural issues 

The temperament of your pet and any underlying behavioural issues must be taken into account. 

The long-term effects of the implant are still being studied, therefore we cannot say for sure that they are a safe and reliable long-term option. 

The risk of potential side effects such as allergic reactions and hormonal imbalances needs to be considered. The risk of these adverse reactions needs to be weighed up against the proposed benefits of using an implant.

The effects of neutering implants will vary between dogs, cats and other companion animals. No two pets are the same. It is very important that owners are well informed about the recommended uses and disadvantages of implants before opting to use them. 

Neutering implants do have a place in veterinary medicine, as more research is carried out, hopefully, their safety and effectiveness will be further established. 

Final Thoughts 

Neutering implants do offer a less invasive alternative to surgical neutering for pet sterilisation. However, in the grand scheme of things, they are still very much a developing technology with many limitations. If you are considering them for your pet, always consult your vet first and foremost to discuss the individual needs of your furry friend. Your vet will be able to enable you to weigh the risks and benefits of using neutering implants  

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