Birth Control for Dogs: How Does it Work?

I’m no expert, but I’m pretty sure a box full of puppies is the single cutest thing in the world.

That said, puppies are needy little things, who require a ton of care – care that many people are unable to provide.

So, it is important to take responsibility for your pet’s reproductive system and make sure that your pup doesn’t become a new mom or dad unless you are in a position to provide for the youngsters and find them all good homes.

Fortunately, there are a few things you can do to prevent your dog from bringing any unintended puppies into the world. We’ll discuss the best birth control options for dogs below and explain the various pros and cons of each.

Hopefully, this will help prevent your search history from looking as bizarre as mine now does.

Birth Control for Dogs: Key Takeaways

• There are a few different types of birth control that are effective for dogs. This includes everything from spaying and neutering to barrier-style contraceptive devices.
• You’ll have to discuss the best birth control strategy for your specific dog with your vet. Surgical sterilization is the easiest (and most common) strategy many owners use, but some dogs may be better served by other types of contraceptives.
• You may see DIY dog contraceptive solutions and abortion-inducing techniques online, but you’ll want to avoid these. Many are dangerous, and few work reliably.

Basic Canine Birth Control Options: How to Prevent Pregnancy in Dogs

There are a few different types of birth control available for your pup. They primarily fall into one of three categories, which we’ll mention here and then discuss in greater detail later.

• Surgical Sterilization – Typically called spaying (in the case of females) or neutering (in the case of males), surgical sterilization is the most common type of birth control most owners choose. And, if you adopted your pooch from a shelter, your dog probably already has been “altered” or “fixed” (colloquial terms for being surgically sterilized).
• Medical Birth Control – There are a few medications that can cause dogs to become temporarily or permanently infertile. The exact medications available will vary depending on the country in which you live, your dog’s health, and a million other things, but they’re a helpful option for some pups.
• Barrier Contraception – Barrier-style contraceptives for dogs utilize the same basic principle that barrier-style contraceptives do for humans – they prevent the sperm-egg union that will lead to new puppies. But (thankfully), barrier contraceptives for dogs are a bit different than the ones people use. So, you won’t have to get uncomfortably intimate with your pupper to use them.

As with most other aspects of dog care, none of these options are perfect.

They all have strengths and weaknesses, and some work better in some situations than others. We’ll talk about each of these three contraceptive options in greater detail below. 

Spaying or Neutering: The Standard Dog Birth Control Option

Spaying and neutering are undoubtedly the most common types of birth control used in dogs. Both procedures are surgical in nature, and your dog will be placed under general anesthesia during the operation.

Most vets consider male dog birth control surgery (also known as neutering or, technically speaking, an orchiectomy) to be the quicker and easier procedure.

After anesthetizing the patient, a vet makes an incision in front of the dog’s scrotum and removes both testicles, as well as some of the related structures. The incision is then sewn back shut, and that’s that. Do note that the scrotum is usually left in place, and it’ll usually shrivel up over time. However, if the scrotum is particularly large, the vet may remove it too.   

Spaying operations are a little more complicated. In fact, there are two different surgical options for sterilizing female dogs.

• Ovariohysterectomy – Both ovaries, the fallopian tubes and the uterus are removed.
• Ovariectomy – Only the ovaries and a portion of the fallopian tubes are removed. The bulk of the uterus is left intact.

Both types of spaying operations are effective. Ovariohysterectomy is more common in the US, while ovariectomy is more common in Europe, but you can usually get either procedure performed, regardless of which side of the pond you live on. In either case, the dog will be sterile after the procedure, and she won’t experience a heat cycle at all.

Neutering and spaying procedures are both permanent and almost 100% effective when performed correctly.

They also offer several health benefits:

• Neutering, for example, can help reduce mounting and wandering behaviors in males, and it may reduce a dog’s chances of developing prostate cancer.
• Spaying may provide a variety of health benefits, but it is most notable for reducing the risks for uterine infections and a few different cancers.

Spaying and neutering are not, however, risk-free.

Surgical complications are always a possibility with any operation, and some females develop incontinence following an ovariohysterectomy. However, the risks of this may be reduced if a dog is allowed to experience one complete heat cycle before the spaying operation.  

Additionally, some research suggests that surgical sterilization may be associated with an increased likelihood of joint issues and some types of cancer (particularly in large dogs). This is thought to be related to the complete cessation of testosterone production in castrated males.

Ideally, dogs are spayed or neutered relatively early in life, as this tends to maximize the health benefits of each. Most vets recommend altering dogs between four and six months of age, but some shelters perform the operation on two-month-old puppies.  

Make sure to read our full guide to the pros and cons of spaying and neutering for a more in-depth discussion, as well as our collection of dog spay and neuter stats.

Medical Dog Birth Control Options

There are a few different medical forms of dog birth control, which are administered orally or via an implanted device.

We’ll discuss the most commonly used ones below.

Megestrol Acetate: Dog Contraceptive Pill

Initially developed to treat cancer and wasting syndrome in humans, megestrol acetate is also used as a birth control medication for female dogs.

It is also used for treating a few other health conditions, including false pregnancy and some skin conditions. Also, because it tends to suppress testosterone production, it is occasionally used to eliminate sex-related behavioral issues in males.

Megestrol acetate is a relatively old drug, which was originally developed in the late 1950s, but it wasn’t marketed as a dog contraceptive in the US until 1974. Originally sold under the brand name Ovaban, the Megestrol for dogs is now available as a generic medication.

Megestrol acetate comes in tablet form, but it is not a dog sterilization pill. It is part of a class of drugs known as progestins, which are chemically similar to progesterone – a naturally occurring hormone that plays an important role in your dog’s reproductive system.

Megestrol acetate is administered at the beginning of a dog’s second heat cycle (it should not be used until a dog has successfully completed her first heat cycle), during a stage known as proestrus. It is given over a short period of time, and it triggers a four- to six-month delay in the onset of the next heat cycle.

Megestrol for dogs is not intended for long-term use, and veterinarians do not recommend using it for more than two consecutive heat cycles.

Accordingly, it is really only appropriate for dogs who will either be deliberately bred or will be spayed at a later time.

Megestrol acetate is associated with a few important health risks and side effects. Some of the most notable include:

• Mammary gland enlargement
• Mammary cancer
• Behavioral changes
• Weight gain
• Lethargy

It can also cause birth defects or labor difficulties if administered to pregnant dogs.

Mibolerone: Liquid Dog Contraceptive

Mibolerone (also known as dimethylnortestosterone) is an androgenic steroid that is used to suppress the estrus cycle of female dogs. It does so by counteracting the effects of estrogen and progesterone.

You must begin administering the drops at least one month before the beginning of the proestrus stage of your dog’s heat cycle to be effective.

Mibolerone has been around for a while, as it was first produced in 1963. The medication is available in liquid form, and it is administered orally. Mibolerone for dogs is sold under the brand name Cheque Drops. Dogs of different sizes (and even different breeds) require different dosages of the medication.

Mibolerone only delays estrus about 90% of the time, so it is not completely effective. It can be used for up to two years, but it isn’t appropriate for life-long use.

Additionally, it is not recommended for dogs who will be used in breeding programs at a later date, as it can delay subsequent heat cycles for up to 200 days. False pregnancies are also common after ceasing the medication.         

Mibolerone is not safe for all dogs. It is contraindicated for dogs with kidney or liver problems, and it isn’t recommended for some breeds (most notably, Bedlington terriers). It is also associated with a variety of side effects, including aggression, oily skin, vaginal discharge, and urinary incontinence.

Mibolerone for dogs can also cause lesions to develop in the reproductive tract, and it is known to trigger clitoral swelling (although this often resolves after the medication is stopped).

Medroxyprogesterone Acetate: Dog Contraceptive Injection 

Medroxyprogesterone acetate is a synthetic version of the drug progesterone, so it works in roughly the same way that megestrol acetate does.

The drug is available in generic forms, but it is best known by either of its name brand formulations – Provera or Depo-Provera.

This medication was first developed in the 1950s, and it is used for birth control, as well as the treatment of some other hormone-related ailments in humans. In dogs, it is used to address behavioral problems, such as aggression, and to delay the onset of estrus.

The medication is available in several forms, but it is most commonly administered to dogs as an injection. Two dosage strengths are available, which last three or four months, respectively. The medication is not FDA-approved for use in pets in the US, but some vets will prescribe it for “off-label” use.  

Unfortunately, there are a number of side effects associated with medroxyprogesterone acetate. Among other things, it can trigger mammary tumors, diabetes, weight gain, and lethargy. Some vets even discourage its use completely in intact females, as it may trigger potentially dangerous uterine infections.

Medroxyprogesterone acetate is also used to diminish the sex drive of males, and reduce some sex-related behaviors, such as roaming for mates.

Suprelorin (Deslorelin Acetate): Dog Contraceptive Implant

Deslorelin acetate is a medication that suppresses gonadotrophins and testosterone in dogs. It is used for a variety of different purposes among veterinarians, including the treatment of adrenal problems in ferrets, and as a birth control drug in dogs.

The medication (better known by the brand name Suprelorin) is a dog contraceptive implant that is available in two different sizes, to trigger infertility for either six or twelve months.

It is only approved for use in male dogs, but several studies have found it effective for female dogs (and other wildlife species), and some vets have prescribed it for “off-label” use.

This medication is very similar to the gonadotropin-releasing hormone your dog’s body already products. The implant works by releasing this chemical slowly over time, which effectively prevents his or her body from producing the hormones necessary for proper reproductive function – including testosterone.

This means that, in addition to causing temporary infertility, deslorelin acetate also triggers the same kinds of behavioral changes in males that some other medications and surgical procedures do.

Zeuterin (Zinc Gluconate and L-Arginine): Dog Sterilization Injection

Zeuterin is the only FDA-approved sterilant for dogs in the US. Designed to permanently sterilize male dogs between 3 and 10 months of age, the medication is injected directly into each testicle (ouch).

According to the manufacturer, the procedure takes only a few minutes, causes little pain and requires no anesthesia.

However, and on behalf of male dogs everywhere, I’d suggest that anesthesia is probably desirable any time you start poking around such delicate areas with sharp instruments. In fact, some vets appear to agree, and a few even call the treatment “barbaric.”

The drug kills any sperm present and damages the testicles. Most dogs will experience swelling for a few days following the injection, while some will – get this – experience swelling that lasts months.

Unsurprisingly, inflammation follows, making it impossible for future sperm to travel throughout the duct system. Eventually, the drug causes testicular atrophy, but the degree of atrophy achieved varies, and it isn’t always visually obvious.

After administration, Zeuterin reduces the levels of testosterone produced by a treated dog’s body. However, most dogs begin to produce some testosterone again, so this contraceptive approach does not reduce the incidence of prostate problems or other diseases affected by testosterone.

It is also unlikely to trigger the behavioral changes, such as reduced aggression, that are sometimes desired (although behavioral changes following sterilization are often unpredictable).

On the flip side, this means that it may be less likely to trigger some of the hormone-related health problems that are thought to result from castration. 

To administer Zeuterin, vets must become certified by the distributor. To do so, they must complete a five-hour course detailing the procedure.

The business side of the veterinary drug production and development has not been kind to Ark Sciences, Inc., the company who manufacturers the medication. They stopped producing the drug in the United States in 2016.

The medication has a two-year shelf life, so no doses are available anymore. The same drug is still sold outside the US, under the brand name Esterilsol.

Calcium Chloride/Ethyl Alcohol Injection

Some vets have experimentally administered calcium chloride/ethyl alcohol injections to sterilize dogs in roughly the same way that Zeuterin is used.

It reportedly causes permanent and irreversible sterility in male dogs, but the treatment is not approved by the FDA.

Other Birth Control Medications

There are a few other birth control medications that are used in some other parts of the world, and a few that are no longer available. Additionally, it is important to note that this is a relatively fertile (ha!) area of research, so it is wise to discuss any new or recently approved birth control medications available.

Some researchers have also found that ultrasound can be effective for sterilizing male dogs. However, it requires repeated applications and the dogs must be anesthetized prior to the procedure, which eliminates many of the benefits of surgery-free birth control methods.

Additionally, this method does not seem to have gained widespread acceptance in the veterinary community.

A Note Regarding Off-Label Dog Birth Control Use

As can see, a number of the drugs used for birth control in dogs are not FDA approved for such use. However, veterinarians often have the legal authority to use medications in non-approved ways (although there are some restrictions).

So, just because some of these medications are not approved for use in the US doesn’t mean that you won’t be able to get your vet to use them to treat your pet.

Vets are all individuals, and they have varying comfort levels regarding off-label use, so you’ll just have to discuss the options your vet is willing to implement.

Additionally, in rare cases, it may even be worthwhile to travel overseas with your pet to obtain one of the medications that are not available in the US.

And for the record, we have readers from all around the globe, so while we tend to focus on American dog owners, we also try to provide information for our friends in other parts of the world.

Barrier-Based Birth Control Methods: The Original Dog Anti-Breeding System

A few different barrier-based contraceptives for dogs have been tried, but few have proven reliable and effective.

Intrauterine devices, for example, have proven to be problematic, and condoms present a variety of challenges that make their use impractical.

If you think making eye contact with your dog while he’s pooping is awkward, just imagine how you’d feel getting him “suited up” for a night on the town. You’d never be able to look him (or yourself) in the eye again.

There is at least one dog chastity-belt-like option available, which may prevent your dog from having intercourse. However, based on the photos some owners have provided of the product in action, it doesn’t always work.

You may be able to fit a female dog with a period panties or use a belly band on male dogs to prevent them from having sex, but neither solution is entirely effective. At best, these should be considered temporary, stop-gap options.

Reasons Spaying and Neutering Dogs Isn’t Always Appropriate

The bulk of the veterinary community recommends that most owners spay or neuter their pets. Not only are both operations effective forms of birth control, they also offer a number of health benefits.

However, there are some cases in which spaying and neutering aren’t ideal. A few of the most common examples are discussed below.

• Dogs who cannot tolerate anesthesia
• Dogs who are poor candidates for surgery
• Dogs who are slated for future breeding trials
• Owners who are concerned about personality changes following sterilization

If any of the descriptions above apply to you or your pup, you may be forced to consider medicinal or barrier-style contraception for your canine.

Ultimately, there are pros and cons to having your dog altered, so be sure to discuss your decision with your vet. If you’d like to read more about the pros and cons of spaying and neutering, check out this article on the subject (page 14), authored by K9 of Mine contributing veterinarian Joanna de Klerk.

Natural Birth Control for Dogs: Home Remedies & Natural Options

Unfortunately, there are no safe and effective methods of “natural” birth control for dogs. After all, dogs have evolved over millennia to reproduce as effectively as possible!

However, that doesn’t mean you may not see purported herbal birth control remedies in some of the less-responsible corners of the internet. Just pretend like these don’t exist, as they’re unlikely to be effective and they may cause your dog to become quite sick. 

Dog Birth Control FAQs

The very notion of dog birth control is a bit strange, and many owners have questions about the issue. We can’t answer every possible question, but we’ll try to address a few of the most common below.

Dog Birth Control: The Takeaway

As you can see, there are alternatives to spaying and neutering, which may be a better birth control method for some dogs.

None of the options available are completely perfect or without drawbacks, but you should definitely discuss these options with your vet if they seem more appropriate for your pet’s circumstances.

Have you ever used an alternative form of birth control for your dog? We’d love to hear about your experiences!

Tell us the good and the bad of your chosen method, as well as any ways it appeared to alter your dog’s personality of behavior. Your experiences may help some other dog lover make the best choice for their pooch!