Last Updated: 10/06/2025
Dogs on Heat
Learn how to manage heat in your dogs.
Author: Dr Chelsi Kuebler BVSc
Reading Time: 16 minutes - medium read
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Last Updated: 10/06/2025
Learn how to manage heat in your dogs.
Author: Dr Chelsi Kuebler BVSc
Reading Time: 16 minutes - medium read
Want to know more? Check out some of our other articles:
Being "on heat" or "in season" refers to when your pet is going through the oestrus part of her reproductive cycle. It is during this time that she can become pregnant. Discover everything you need to know about your dog being on heat.
The average age of sexual maturity in dogs is 6 months. However this can vary based on breed and genetics. Some smaller breed dogs can go into heat as early as 4 months of age, whereas large breed dogs tend to mature later and may not have their first heat until they are over 18 months old!
The frequency of "heats" or "seasons" also depends on breed size. Small breed dogs can go in heat 3-4 times a year, whereas giant breeds may only go on heat once a year.
Most heat cycles last anywhere from 1.5 to 4 weeks. Although your dog may not be displaying heat behaviours, she can fall pregnant anywhere during this time frame. Therefore it is important to keep her isolated from other dogs (males especially) to avoid mating and any unusual behaviours from other females. You will know when her cycle is over when there is no longer any discharge, and her vulva goes back down to a normal size.
The signs of heat in dogs can vary from dog to dog, but they will generally include:
The best and easiest way to prevent pregnancy in dogs is to get your dog desexed. Your local vet should offer this procedure. It is a routine surgery and in most cases is easy to do and with little risk.
However, if your vet has recommended waiting to have your dog desexed, maybe because she is a large breed, the best way to avoid becoming an unwanted pet-grandparent is to make sure your in-heat female dog isn't mated. As stated above, keep her isolated from other dogs while she is on heat. This means avoiding dog hotels, doggy daycare, dog parks, and the beach. Stay clear of other dogs while on walks. It is also a good idea to avoid leaving her outside unsupervised as male dogs can be quite determined and figure out a way into the yard.
If there has been an accidental mating, contact your vet immediately. You can book your dog in for an injection that will terminate the pregnancy.
Our experts continually monitor the health and wellness space and we update our articles when new information becomes available.
Contributing Author, BVSc
From a very young age I knew I wanted to help animals. As I grew up I considered other career paths but always circled back to my dream of becoming a vet. I’m from Minnesota originally but I came to Australia for vet school and graduated from the University of Sydney in 2019. Since graduating I have worked in both small animal and mixed practice. We have 2 pets – a dog and a cat. Ahsoka is our blonde Kelpie mix and Binx is our charcoal tabby Domestic Shorthair.
While heat cycles are a natural part of caring for an undesexed female dog, there are a few things you can do to ensure both you and your dog are set up for success.
