How to Prevent Dog Pregnancy After Mating

Updated: 8/2/2021
Nothing beats cute, cuddly and totally irresistible puppies. But while puppies are a fantastic amount of fun, puppies are extremely time-consuming and cost an arm and a leg to care for, so being able to decide when your dog has them is a worthwhile endeavor. Being pregnant is a fantastic experience for your dog, but it is also tough and exhausting, not to mention, pregnancy always brings with it a risk of complications.

But what should you be looking out for if you think your dog may already be pregnant? Can you see a visible swelling in your dog’s stomach? Does your dog have an increased appetite? Have the nipples grown? Does your dog seem lethargic, or is she showing signs of a personality change? All of these can be indicators that your dog is carrying some extra passengers.


When female dogs are in heat, male dogs can smell the hormones and read the telltale signs that they are ready to mate. Often, the mating process takes a surprisingly short amount of time and can take place without pet parents even being aware it has happened. Dogs that are not on leads when they are on walks, or even dogs that are left tied up outside a shop, are all at risk of unexpected mating.

Fortunately, there are still steps you can take as a pet parent to prevent pregnancy after mating. The first option is spaying during pregnancy. Spaying is a process in which the dog’s ovaries and uterus are surgically removed. Spaying can take place early in the pregnancy and the cluster of cells developing into puppies can be removed as well.

It should be noted spaying during pregnancy brings with it a higher chance of complications. The surgery takes longer than regular spaying and brings with it an additional charge, plus the scar left by the surgery will be bigger than the one from a normal spaying procedure. However, this is a long term, 100% effective preventative measure to take if you don’t want your dog to get pregnant after mating, or ever again.


Most dogs, given the opportunity, will end up mating when the female is in heat. A whopping 40% of female dogs will fall pregnant after just one mating session! That incredibly high number means you are at considerable risk of having a litter of unwanted puppies if you are not careful. Thankfully, there are still a number of relatively safe means to preventing pregnancy after mating.

One such option is known as a ‘mis-mating injection.’ If you suspect your dog has only mated in the last 22 days, then an injection of Alizin, an antiprogestagenic compound can be given which will terminate the growing cluster of cells inside your dog. If given this early in the pregnancy it will be 100% effective. It can also be administered later on in the pregnancy, but it is less likely to be as effective.

This is an effective preventative measure to take, especially if given early. However, it is not a long-term solution, it will not prevent your dog getting pregnant again in the future. If you are looking for a long-term solution, then the previously mentioned spaying method is advisable.

Veterinary Abortion

When your dog is in heat, the smell and hormones released will be picked up by male dogs from a considerable distance. Male dogs can be extremely driven and creative when it comes to getting access to female dogs in season. So even responsible pet parents who have big breeding plans will occasionally come across unwanted pregnancies. But even if spaying and mis-mating injections are not avenues you want to go down, then there are still other options available to you.

A veterinary abortion is a viable, effective way to eliminate pregnancy after mating. But this is not an option that should be taken lightly. The risk of complications is much higher and it should be done only when it is too late for other options and pregnancy is not a feasible option. A veterinary abortion can be done either as a surgical procedure, or abortifacient medications can be administered.

Abortions of this type put considerable strain on your dog’s body and it is not uncommon for dogs to need to stay in for observation for up 7 days after the procedure. It is also a very costly termination option. While it is extremely effective, it will not prevent your dog getting pregnant again further down the line.

Effects of Preventing Pregnancy in Dogs

The effects of preventing pregnancy after mating are substantial. A litter of puppies is a huge amount of hard work. The average litter is 5 or 6 puppies, who will not be toilet trained, who will need injections, care, and looking after for the first months of their life.

Preventing pregnancy will also save your dog from considerable stress and the risk of pregnancy complications. Puppies are also extremely expensive when you factor in medical bills, vaccinations, food and a range of other costs. Many people have to take weeks off work to look after puppies in the early weeks, so preventing a pregnancy all together has far-reaching consequences.

If you do choose to proceed with your dog's pregnancy, check out our pet insurance comparison tool. Brought to you by Pet Insurer, Wag! Wellness lets pet parents compare insurance plans from leading companies like FIGO and Nationwide.

Take Home Points

Dogs are incredibly successful at mating quickly and in unexpected situations. Even careful pet parents will likely face an unwanted pregnancy at some point. However, there are a number of options available to you even after your dog has mated to prevent pregnancy ensuing. The first long-term solution is spaying. This will prevent your dog becoming pregnant on this occasion and ever again. A mis-mating injection is also effective if used early on, but will not prevent future pregnancies. Finally, a veterinary abortion should be used only as a last resort, as it will put serious stress on your beloved dog.

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