How Long Is a Dog in Heat

how long is a dog in heat?

A dog heat cycle can be challenging for both a pet and her owner. Dogs can feel confused and out of sorts. Owners might well wonder what they can do to make the heat cycle more comfortable for a dog in heat. It’s a tricky time.

Understanding what happens in a dog’s heat cycle is going to help. Preparation is key so read on for everything you need to know about the estrous cycle and dogs in heat.

When Do Dogs Have their First Heat Cycle?

Dogs will have their initial estrous cycle when they get to puberty. You can also refer to this as the reproductive or heat cycle.

Each cycle has several different stages. The estrus stage refers to the time when a dog can actually get pregnant. This is the moment when we would typically say a dog is in heat.

On average, dogs will reach puberty by around 6 months of age. There can be variations depending on their breed. Smaller types of dogs, for example, often have their first estrous cycle at an earlier age. Large breeds may not come into heat for the first time until they reach 18 months to 2 years of age. It’s a wise move to keep a record during these early days.

How Often Do Dogs Come Into Heat?

The majority of dogs will come into heat twice a year. The timeframe between the cycles can vary depending on the breed. Small breeds of dogs may have 3 heat cycles a year. Large breeds sometimes only have 1 heat cycle a year.

When dogs first begin to have their cycles, it is normal for them to be a little irregular. It can often take up to 2 years for a female dog to begin having regular cycles.

There is no particular breeding season for dogs. That’s except for Tibetan Mastiffs and Basenjis that tend to come into heat during the Spring.

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What Are the Different Stages of a Dog’s Estrous Cycle?

The reproductive cycle of a dog has 4 different stages.  These are proestrus, estrus, diestrus, and anestrus. Each stage comes with different types of behavior as well as physical and hormonal changes. 

Proestrus: The average length of this stage tends to be 9 days, but sometimes it can vary from 1 day to 27 days. Although this is the moment that a male dog will get attracted to a female, she will not be receptive to his attention.  

A female dog’s estrogen levels will peak and the follicles or egg cells will develop.  The vulva will typically become swollen with blood visible in any discharge.  

Estrus: This is the fertile period when a female will be receptive to the male. Again, it tends to last 9 days but can range from 4 to 24 days. There will be less blood in the discharge from the vulva.  Estrogen levels will drop and progesterone levels will begin to rise. 

Diestrus: During this stage which lasts for about 2 months, the female will no longer be receptive to the attention of a male. Estrogen levels will be low and progesterone will peak after about a month and then drop back.

Anestrus: This stage will last for the months until the next proestrus stage. The vulva loses its swelling and there’ll be no vaginal discharge. The body uses this time to let the uterus get ready for the next potential pregnancy.  

What Are the Signs of Estrus?

Because the estrus period is so significant, it’s worth taking a closer look at some of the symptoms you’d expect to see. 

The first sign of estrus is swelling or enlargement of the vulva. This swelling is not always noticeable. In lots of cases, a bloody vaginal discharge would be the first visible sign that a pet has come into heat. Sometimes this discharge doesn’t appear until several days after estrus has started. The amount of discharge will vary depending on the dog. 

You’ll notice that the vaginal discharge changes color and appearance as the cycle progresses. Initially, the discharge will be very bloody, but as time goes on, it will start to get more watery, less red, and pinker. 

Attracting Male Dogs

A female dog that is in heat will often urinate more often than usual. She may also display marking behavior. This involves urinating in small quantities but on a variety of objects in the home or when outdoors.

It’s during this phase of her cycle that her urine has hormones and pheromones in it that attract her to male dogs. 

Male dogs can detect a female in heat from a great distance and may begin marking your property with their urine in an attempt to claim their territory.

When Exactly Does Pregnancy Occur During Estrus?

A female dog will typically ovulate at around the time her vaginal discharge becomes watery. This acts as a marker for her most fertile stage. It’s the moment when she will be most receptive to breeding. 

It’s possible for sperm to survive for a week in the reproductive tract and still retain the capability to fertilize the eggs. It is therefore possible for a female to get pregnant at any point while she is in estrus. 

During coitus, part of a dog’s penis enlarges. At the same time, the female’s vaginal muscles contract, stopping the male from withdrawing. 

Breeders consider this “tie” as desirable but a pregnancy can happen without a tie. Ties tend to last around 5 minutes. Once they have started, it is almost impossible to separate the 2 dogs. In fact, if you try to do so, you could cause an injury.

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How Long Does A Pregnancy Last?

Pregnancies will last for around 9 weeks or 63 days in a dog. You can read more about what happens during pregnancy here.

A dog has to be in heat to get pregnant. It’s not always obvious when she is in heat. If you think your dog could be in heat, or it’s about the time that she should be, you should take precautions to prevent her from becoming pregnant.

Should I Let My Dog Have a Heat Cycle Before Spaying?

From a medical perspective, there are no reasons for letting a dog have a litter before getting spayed. Some dogs, particularly larger breeds, however, may benefit medically from delaying their spay surgery until after their first heat cycle.

There is general agreement that spaying will raise the life expectancy of a dog. Dogs can become pregnant during their very first estrous cycle. Dogs are not fussy about who they mate with. It’s not uncommon for a brother to try to breed with his sister or a son to breed with his mother.

There is no truth in the belief that female dogs become more friendly and sociable if you let them have a litter of puppies.

How Do I Care For a Dog In Heat?

Your dog may display different types of behavior when on heat compared to other times of the year. She might be clingy and in need of a little more care and attention than usual. 

Keeping your dog happy and distracted will help. Lay on plenty of entertainment by playing and giving your dog things to do around the house. This could include a game of “hide and seek” with the prize of a treat-filled toy. More walks but avoiding contact with other dogs by using a leash can help to keep her calm.

Dogs in heat can often seem anxious and restless in part because of fluctuating hormone levels. Make the home calmer by playing gentle music. Ensure she always has a comfy warm bed in her favorite spot.

Always Use a Leash!

You may need to manage the bloody discharge. This could show up anywhere around the house. You could think about reusable or disposable diapers. Some females go off their regular food when they’re in heat, so it’s important to make sure your dog eats well.

Never scold your dog if she has accidents in the house. For her, this is part of the natural “in heat” cycle. More frequent walks might help. 

Sometimes females in heat may try to escape in order to find a male. Make sure this can’t happen from your home and never let your dog outside unless she’s on a leash.

Always Check in With a Vet

Being in heat can be a challenging time for both a dog and her owner. If you have any questions related to a dog’s reproductive cycle, do get in touch with us. We have a team of qualified vets ready to take your call whatever the time of day.

Many owners prefer to take on a spayed pet to eliminate all the issues that go with being in heat. If you’re considering this option, we can help you decide.

We have lots more useful articles about dogs in our blog section. Don’t forget to check out our pregnancy calculator here.

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