Your Dog’s Heat Cycle

Your Dog's Heat CycleWhen you own a female dog, you come to dread the menstrual cycle. Partly because she will attract male dogs from far and wide and secondly because she will leave a trail of blood spots all over your home, possibly on the furniture. Fortunately, there’s a problem solver for both issues.

Your female dog may appear to have a menstrual cycle like a woman’s cycle, but to be accurate, your dog has what is called an estrus cycle (known more commonly as a heat cycle – your dog is in or on heat) with a different cycle pattern to women.

A dog that is sexually mature will go through a heat cycle twice a year, although some only reach the cycle once a year. The cycle has four distinct stages called: proestrus, estrus, dietrus and anestrus.

The Estrus Cycle

The whole cycle typically takes between six and eight months, but in some breeds of dog it takes a full year. The length of the cycle depends upon the dog’s age, health and breed. The cycle will continue throughout their lifetime as dogs don’t go through a menopausal stage as they grow older. The difference with dogs is that their estrus cycle increases little by little as they get older.


The first part of the estrus cycle starts with a nine day phase called proestrus. The dog’s vaginal zone swells and starts to pass a bloody discharge. This is not the menstrual cycle, a fact which often causes confusion. The dog’s body starts to get ready for a possible pregnancy, but won’t look for a male partner at this time.


The second part of the cycle, called estrus, lasts around another nine days. This is when the dog ovulates and looks for a male partner. This stage may begin at around six months of age.

This is when you need to ensure that your dog can’t get out of its compound or be let off its leash if you don’t want your dog to become pregnant. Female dogs will attract almost any male dog during this time to allow breeding.


With diestrus, you are into the third part of the cycle. This 70 to 80 day period starts whether the dog is pregnant or not. They will feel hormonally pregnant which gives the experience of the false pregnancy. They won’t be looking for a male, but might act as though they are pregnant by using toys and other animals as their puppies.


The last part of the cycle is called anestrus which lasts for up to 130 days. Female dogs never accept a male dog during this time, as this is the time when the dog rests from the pregnancy (whether real or false) so the body can repair itself before starting the whole process again.

Dog breeding

No doubt you have given thought to whether you are going to allow your dog to breed. Some will suggest that the natural cycle should be allowed while opponents will suggest that there are too many dogs in the world already and you should be responsible in only allowing selected breeding.

If you are going to take your dog to the veterinarian, it’s best to wait until at least 30 days after the estrus cycle has completed, providing your dog isn’t pregnant.

Experience shows that to maintain a dog’s health later in life, it is recommended that spaying be deferred until around the 10-12 month age.

If you do intend to breed your dog, you should visit your veterinarian to have complete medical checkups for both breeding dogs. This will establish that they both have perfect medical records and will not pass on any diseases to puppies.

Obviously, the breeding program you select for your dog should not endanger its health. It is probably best to wait two years before the breeding program starts.

About the blood

Most dog owners worry about the bloody discharge, particularly if they have a dog that lives indoors. Buy some dog diapers. This will prevent the blood reaching your carpets and furniture. It will also help in reducing the odor problem often associated with this part of a dog’s heat cycle.