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How Long Is A Dog In Heat

Whether you have adopted a female dog or you haven’t gotten around to spaying your female puppy, and now your pup is in heat. Now, you are asking how long is a dog in heat.

A dog’s heat cycle lasts for three weeks or 21 days to be exact.

During that period there are actually only three to four days when she can actually breed with success and get pregnant.

The problem is, if you do not want your dog to become pregnant, it is very hard to tell exactly which days those are.

To avoid an unwanted pregnancy, she will need to be kept guarded at all times!

How Long Is A Dog In Heat

What Age Do Dogs Have Their First Heat Cycle

Different breeds of dogs reach puberty at different ages.

Smaller breeds mature earlier and can reach sexual maturity as early as 6 months.

Larger breeds may not experience their first estrus cycle until 18 months to two years.

How Often Do Dogs Go Into Heat

Female dogs go into heat approximately every six months. However, there are exceptions to the rules.

Some dogs may be “in season” only once a year and some more often than twice a year.

This is especially true with females that spend time around other females that may be in heat. You see this in breeder situations.

Golden Retriever dog sitting on a couch

Physical Signs Your Dog is Going Into Heat

One of the first and most obvious signs that your female dog is going into heat is that she is paying a lot of extra attention to her tail and genital area. She may be licking and sniffing.

You may also notice a swollen vulva, vaginal discharge, or bloody discharge when the heat cycle begins in earnest.

Some female dogs never exhibit bleeding as a symptom of heat. So, you should not assume your dog is not in heat if you do not see this.

This is referred to as “dry” heat and your female can still get pregnant at this time.

The second week of the heat is when she will be most interested in mating.

She will also be urinating frequently to attract every dog within a twenty-mile radius it seems.

Pet parents should never leave her outside unattended.

Even with a fence, males will either find a way to a female in heat or she will find a way out. The call of nature is extremely strong.

Behavioral Signs Your Dog Is In Heat

Behavioral signs of a dog in heat are usually the most obvious indicators that your pup is entering her heat cycle.

You may notice that she is more agitated and restless, or she could be extra clingy and affectionate than usual.

She might even be pacing around the house like a wild animal!

Female dogs in heat will also show an increase in sexual behavior, such as humping or mounting other animals or items in the house.

This is normal and should be expected, but you should try to discourage this behavior as it can lead to aggression from other dogs.

Finally, female dogs in heat may also become very vocal and bark or whine more than usual.

This is her way of trying to attract male suitors, so it’s important to keep her away from other animals while she is in heat.


For cleanliness purposes, consider using a pair of dog panties sold for this purpose.

Alternatively, you can simply insert a Maxi-thin pad into a small pair of child’s underwear.

Change the pad as necessary and don’t forget to remove the panties when she goes out to relieve herself.

Using store-brand sanitary pads is a much cheaper alternative than buying the pads they sell in large pet-care stores.

You can also use either disposable doggie diapers or washable cloth diapers.

Jack Russell Terrier dog

Preventing Unwanted Puppies

If you do not want your dog to have puppies or you do not want to continue going through messy heat cycles then spay surgery is the answer.

Spaying is an everyday operation in which her uterus and ovaries will be removed.

With the overpopulation of unwanted pets today, breeding more should be well thought out in advance anyway.

If you have been a reader long, you know I advocate for spaying and neutering to avoid adding to the unwanted pet population!

In addition to preventing unwanted pregnancies, spaying offers other health benefits such as preventing uterine infections and mammary cancer.

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