How Long Can a Dog Stay in Heat? Here’s how you’ll know her cycle is over

How often do dogs go into heat? Right from around six months old till the dog lives, a dog is bound to experience heat, also known as estrus, every six months. This is when she is the most receptive and is ready for mating. So, how long are dogs in heat, and a few interesting aspects related to the same have been discussed here?


Dogs in heat – Facts and more

As mentioned above, she is ready for mating when the dog is on heat. There will be hormonal changes that will manifest physically as well. You will know that dog is in heat since there will be bleeding, frequent urination, increased alertness, enhanced nervousness, and swollen vulva. She will also be getting closer to the male dogs while she raises the rump and holding the tail by her side. But do dogs have periods? While dogs do not have the menstrual cycle just as human females do, the process of ovulation occurs in dogs.


Dogs in heat – When does it start? 

In smaller breeds, dogs can go into heat as young as just four months; however, the average is around six months. Few of the giant breeds might not get into heat until they turn, at least 18 to 24 months.

Experts give a vital piece of advice,: not to breed the young female dogs while undergoing their first and second cycles. One of the main reasons is their eggs do not mature, and the dogs still do not attain full maturity. As such, it is best to seek the advice of your veterinary about when is the right time to breed your dog.


How long do dogs stay in heat?

When the dog is on heat, it will last for about two weeks to a month. Early in the cycle, it is quite likely that the female dog may not show any interest or may not be receptive to its male companion. However, this period can be shorter or longer.

You will be able to find out when the cycle is over because the vulva will return to its normal size, there will not be any more bleeding, and discharge will stop. But a small window while your dog is on heat will ensure whether its fertility will pay off.

This fertile period may be between nine and ten days once she goes into heat and will stay for around five days. However, it is quite likely that she might get pregnant by the end of the cycle. More about the different phases in the cycle below.


How long does a dog stay in heat – The Four Phases of the Cycle

We have seen above just a sneak peek of the dog’s cycle. In the following paragraphs, let us briefly summarize the four phases of the heat cycle. If you are aware of the details, it will be easier for you to prepare your pet. You will observe changes as the dog passes through these four stages.



This is the beginning of the heat period when the dog’s body gets ready to mate and averages for about nine days and can go up to anything between 3 to 17 days. There will be swelling of the vulva and bloody discharge. You will notice your dog is sticking close to you and getting the tail close to the body. At this phase, she will attract the male dogs but will not be receptive. If a male dog tries to mount her, she may get aggressive.



This is the mating stage and will last for nine days. However, this can be shorter or longer and can go up to 21 days. The flow of blood will be less and stop, and the discharge changes its appearance to a straw color. Ovulation will occur two to three days after mating, and the female dog will attract and accept the male companion. There is increased urination to mark the territory and spread the pheromone,, sending signals of readiness. If a male is available, she will accept him right away.



This stage occurs immediately after the “in-heat” stage and will last for about two months. The dog’s body will either rest and return to normal or get pregnant. The vulva will become of the normal size, and the discharge will stop.



In this phase, the uterus starts repairing itself. As such, it is often known as the uterine repair phase. It can last from 90 to 150 days before the cycle repeats itself from the number 1, which is the Proestrus phase. The above four phases will help you know how long a dog is in heat. 


Can a dog be stopped from getting into heat? 

If you plan to prevent your dog from going into heat, you must get the dog spayed. It is recommended that you spay all the female dogs unless you are planning to strengthen the breed. Spaying also reduces the risk of your mammary cancer, and it will also be unable to get uterine infections or experience the heat cycle.

Spaying can be done while your dog is on heat, and surgery must be avoided because it can get things tricky and messy. However, your pet doctor or veterinarian will best judge which process is suitable for your dog.


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