The Pet Parents® Guide to Female Dogs in Heat

Updated: May 10, 2022

Do female dogs have periods? Like humans, female dogs go changes in their bodies and produce a bloody discharge as a result. This is referred to as a dog heat cycle. A dog in heat is when your female dog hits sexual maturity and managing this can be tricky.

In this Pet Parents® Guide, we’ll talk about what happens when your dog goes in heat, the different stages of the heat cycle, heat cycle abnormalities, what to do when your dog is in heat, and the female dog heat cycle proper management. We will answer questions like: How long does a female dog stay in heat? What are symptoms of heat in dogs? Can you use dog diapers for heat? And more!

Do female dogs have periods? How long do dog heat cycles last?

"Dogs normally go into heat once every six months or twice every year, but this will still vary in each breed."


Your dog going through her first heat cycle means she has hit puberty. When does a dog go into heat? On average, most dogs will have their first heat at six months old, but this will also differ in each breed. According to VCA Hospitals, smaller dog breeds go into heat at an earlier age compared to large and giant breeds. Bigger dog breeds may not come into their first heat until they are eighteen months to two years old.

How Long Are Dogs in Heat?

How long does a dog stay in heat? When going through a female dog heat cycle, your furbaby will experiences different stages. The different stages of a heat cycle in your furbaby will affect your dog’s body & behavior and the behavior of other dogs around them.

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There are four stages in a dog’s heat cycle. Beyond just a dog in heat bleeding, here are the stages of dog heat:

  • Proestrus. This is the start of your dog’s heat cycle. Het hormones are beginning to rise and her body is preparing her for mating. Early signs of the proestrus stage include a swollen vulva and vaginal discharge that will range from being white, pinkish, or reddish in color.
  • Estrus. During the estrous cycle stage, your dog will slowly become receptive to male dogs. During the early part of this stage, males will begin lurking around and female dogs may get aggressive toward them. In the later part, female dogs may get aggressive if there are any female dogs around. They may approach the males around them with their tails raised and held to the side. This behavior is preparation for possible breeding.
  • Diestrus. This is the stage of the heat cycle where your furbaby's body will restore its natural state or prepare for pregnancy.
  • Anestrus. Considered to be the silent phase of a dog’s heat cycle. During anestrus, there will be no signs of hormonal or sexual behavior.

Your dog may become pregnant during her heat cycle. If you bred your dog or a unaltered male dog had access to her, you can look for these signs of dog pregnancy. A female dog completing her heat cycle may also display signs of false pregnancy. There are a few ways to know the difference, but always consult a vet if you are unsure.


In every heat cycle, your healthy dog will fairly display the same heat signs and symptoms. Here are some of the observable changes to expect:

Swelling. As mentioned, a dog who is about to go into heat will have a swollen vulva and this is very noticeable. Your dog’s vulva swollen from heat will look larger than its normal size and swollen during a female dog’s heat cycle.

A lot of licking. A dog in heat will have the urge to constantly lick her vulva. According to Pet MD, this licking behavior is a dog’s innate nature of keeping themselves clean when in heat.

Bloody discharge. Many wonder how long does a female dog in heat bleed. Most female dogs who go into heat will bleed, typically a week or so after the vulva begins to swell. Discharge can range from white to pink to deep red and bleeding will typically last for about 10 days. Some dogs, however, go through silent heat. According to Petful, these dogs actually do ovulate but the specific signs of being in heat, vulvar swelling, and discharge, are not seen. This is considered an irregularity, most of the time you will notice a dog in heat bleeding.

Male dogs lurking around your female. Male dogs are attracted to the scent of female dogs as females produce pheromones when in heat that male dogs can detect even from as far as kilometers away!


How often do dogs go into heat? Dogs normally go into heat once every six months or twice every year, but this will still vary in each breed (as mentioned above). Small breeds may go in heat as much as three times a year and large breeds may only go in heat once a year.

Keep in mind that a dog going into heat does not mean that she is ready to breed. In fact, it is not okay to breed your dog in her first heat cycle. She is still considered to be a puppy and not fully ready to become a mother. Before breeding, you should let your dog pass through her first 2-3 heat cycles depending on age, health testing, and more. Here are some ways you can tell if your dog is ready to breed. Before making the decision to have puppies, it is important to meet all the requirements for responsible dog breeding in order to ensure the health of mother and puppies. 

Keep in mind that older dogs do not go through menopause. But, you may notice some changes in your female dog's heat cycle as she gets older.


Not all dogs go through normal female dog heat cycles. Some may experience heat cycle abnormalities in dogs and these include the following:

  • Absent heat. Your dog missed a heat cycle/s.
  • Silent Heat. Your dog ovulated but does not exhibit the noticeable signs of being in heat. Silent heat can still be detected by male dogs and by medical examinations like progesterone tests.
  • Split Heat. A heat that abnormally stops and then continues after some days or weeks.
  • Prolonged Heat.A heat cycle continuing longer than the average heat cycle duration.
  • Shortened Inter estrus Interval.Heat cycles occur at very short intervals from one cycle to another.
  • Prolonged Inter estrus Interval.Heat cycles occur at very long intervals from one cycle to another.
  • Premature Ovarian Failure. Ovarian functions suddenly weaken or completely stop at an early age.
  • Pyometra. An infection in the uterus that affects your dog’s reproductive tract and heat cycle.
  • These abnormalities may or may not be a cause of concern. If you notice abnormal patterns in your dog’s heat cycle, talk to your veterinarian as soon as possible. It is always better to consult your vet for proper diagnosis and treatment plans.


    With all this information, you might be wondering what to do when your dog is in heat and how you should prepare. Pet Parents® can help you during your dog’s heat cycle to keep your female dog happy and your home clean.

    Diapers for Dogs in Heat

    As the heat cycle comes with vaginal discharge, have your dog wear Pet Parents® Dog Diapers. These diapers for dogs in heat will keep your dog clean and will prevent your house from getting soiled and stained with blood. These washable dog diapers come in packs of three so that you can always have one on hand, one in the wash, and one being used. A diaper for dogs in heat is a must to avoid messes.

    When choosing diapers for dogs in heat, you want to make sure you find the right one. Pet Parents® washable dog diapers are great dog period diapers to keep your furbaby comfortable because they wick moisture away from the surface. Pet Parents® Dog Diapers for heat may also prevent your female dog from getting pregnant with unplanned breedings. Though these diapers are not able to prevent male dogs from lurking around, they can prevent penetration. Having a diaper on a dog in heat can help prevent unplanned litters in unexpected situations. 

    Note: it is still not recommended to let your female dog in heat around males during this time. Diapers for dogs in heat should not be used as a primary form of pregnancy prevention for dogs. Rather, dogs in heat diapers have the extra bonus of being able to prevent penetration from males.

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    Extra Protection

    In addition to diapers for dogs in heat, it is also best to place Pet Parents® Pawtect® Pads in places where your dog usually lays down or sleeps as an added protection. These work as dog period pads over your furniture, bed, or crate. Pawtect® Pads come in a pack of two so that you can always have one on hand and one in the washing machine.

    The Pawtect® Blanket is another great option to keep your female dog comfortable during her heat cycle. Because your female dog in heat may not be feeling her best, it is a great option to provide extra comfort. Plus, Pawtect® Blankets are waterproof! So, even if your female dog in heat makes a mess, it will be trapped in the blanket, rather than your furniture for easy machine washing.

    These Pet Parents® products are made from our proprietary fabric blend and are exceptional in absorbing and locking in moisture compared to other dog diapers for heat and pads in the market.

    Additional Nutrition

    Additionally, adding Pet Parents® SoftSupps® to your dog’s diet, particularly Pet Parents® Multivitamin SoftSupps® will help you be on top of your furbaby’s overall health. These dog multivitamins contain PurforMSM®, one of the purest forms of MSM in the whole world and are also packed with Vitamin A, C, & E. Pet Parents® Multivitamins SoftSupps® provide the nutrients and antioxidant support needed by your furbaby for a healthy immune system.

    Every dog differs in their female dog heat cycle experiences but we, at Pet Parents®, are here to educate you and guide you through all of it. From dog diapers for heat and to nutrition supplements, there are some things you can have on hand to make your female’s heat go as smoothly as possible. By being prepared for heat cycle abnormalities, knowing the stages of dog heat, and knowing what you expect, you will be ready to help your female dog through her special time so you and your dog can live a worry-free, and healthier, happier life ahead.

    "Diapers for dogs in heat will keep your dog clean and will prevent your house from getting soiled and stained with blood."

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