Get

In Your Inbox

Dogster is reader-supported. When you buy via links on our site, we may earn an affiliate commission at no cost to you. Learn more.

Dog Heat Cycle: Vet-Verified Signs, Frequency & Facts

Share

Beagle's swollen genital

Understanding your dog’s heat cycle (or estrus cycle) is paramount if you have an unspayed female at home. Without learning how it works, it is impossible to know what is normal and what isn’t, and how to look after your dog while she is in heat. A good knowledge of your dog’s heat cycle is also important for avoiding unwanted pregnancies and predicting your dog’s behavior. Additionally, if you’re trying to breed your female dog, it’s essential to learn how the canine cycle works to be able to have a successful pregnancy and litter.

This article will help you understand everything you need to know about dog heat cycles, and how to care for your female dog.

divider dog paws 4 oct 2024

When Does a Female’s Heat Cycle Start?

Dog Heat Cycle
You are free to use this image but we do require you to link back to Dogster.com for credit

Different breeds may come into heat (also called into season) at different times. Some breeds mature faster than others and will have their first heat cycle earlier. Smaller breeds typically begin their cycle at a slightly younger age than larger dogs since larger dogs have to take more time to grow. Usually, dogs will become sexually mature and start their heat cycles around 6 months of age.

However, this doesn’t mean that they should start breeding at this time. Dogs are not full-grown at this point. Getting pregnant at such an early age can be detrimental for their health and the pups.

How Often Do Dogs Go in Heat?

Most dogs will go into heat twice a year, every 6 to 7 months. This can vary slightly depending on the breed, with the Basenji or Tibetan Mastiff being reported as typically having only one cycle per year.

Once heat cycles start happening, especially after the second one, they tend to be quite regular. There is no exact time when dogs have their cycles, unlike wolves that have a breeding season from late January through March in the Northern Hemisphere.

Dog smells a dog in heat
Image Credit: sanjagrujic, Shutterstock

What Are the Signs of Heat?

Determining whether or not your canine is in heat requires you to observe her body and behavior. The heat or estrus cycle has four stages. During the first one, called proestrus, you may notice swelling around the genitals and your dog attracting males, but not being interested in them yet. This stage lasts around 7–10 days. Another obvious sign you can notice during this time is an unusual vaginal discharge. This discharge is often bloody and will become lighter in color as your dog enters the second stage, the estrus, or what is usually referred to as being in heat. This is the time when your dog is fertile and will accept mating and it lasts about 9–10 days but it can go up to 3 weeks.

Some dogs may not have much discharge at all, or they may lick it constantly making it almost unnoticeable. It mostly depends on the dog.

Your dog may also urinate more frequently, as they are attempting to spread their scent around. The urine contains pheromones, which will let males know that the females are fertile. At this point, males can smell the female from a great distance away. Dogs in heat may also urinate inside the house. This is normal and instinctual, not necessarily a sign of poor training. Usually, the behavior will stop after the dog enters the next stage of the heat cycle. .

If you need guidance on keeping your dog healthy and comfortable during heat, we suggest you speak to a vet.

If you need to speak with a vet but can't get to one, head over to PangoVet. It's our online service where you can talk to a vet online and get the advice you need for your dog — all at an affordable price!

PangoVet_Mention-in-Content Savings V1

How Long Does the Dog Stay in Heat?

Veterinarian doing an examination of the genitals of a female dog Jack Russell Terrier
Image Credit: Reshetnikov_art, Shutterstock

The entire heat cycle lasts approximately 6 months, but the time where your dog will show signs of being in heat and can get pregnant lasts for 1.5 to 3 weeks. This will vary from individual to individual. If mating occurs, your dog will get pregnant and have a litter of pups around 63 days later.

When Can the Female Become Pregnant?

Female dogs ovulate during estrus, whenever their discharge becomes thin and she accepts males. This is the best time for the female to mate, as it has the highest chance of success. However, sperm can survive in the female’s uterus for up to a week. This means that they may become pregnant after the estrus finishes.

divider dog paws 4 oct 2024

Should a Female Have a Heat Cycle or Litter of Puppies Before Being Spayed?

No. There is no evidence that letting your dog have a litter of puppies before they are spayed will provide any benefits to her. For this reason, we do not recommend letting the female have a litter unless you are a dog breeder. There is a lot more that goes into breeding than simply putting two dogs together.

The exact time to spay your dog depends on her lifestyle and her breed, so it’s best to follow your vet’s guidance on this topic. There is new information nowadays and the general recommendation of spaying dogs before the first heat is not suitable for all.This is because spaying the dog affects their hormone levels, which can have an effect on their development. However, you should be very careful for your dog not to become pregnant while you wait for the right time for her surgery. Getting pregnant can also be worse for their health, especially if they are too young.

See also:

divider dog paws 4 oct 2024

Final Thoughts

Understanding your dog’s physical and behavioral changes though her heat cycle, is important to know what is normal and what isn’t so you know when your vet’s input is necessary. If you’re not planning to breed your dog, you should speak to your vet about the best time to have her spayed to prevent unwanted pregnancies and serious health issues in the future.


Featured Image Credit: Sigma_S, Shutterstock

Want content like this delivered to you?

Sign Up For Our Newsletter

News, insights, expert advice, and everything dog

* By submitting, you agree to our Terms & Conditions and Privacy & Cookies Policy.




How useful was this post?

Click on a star to rate (you can leave written feedback after clicking submit)

Help us improve Dogster for pet parents!

Your feedback really matters.

What did you like about this post? Also how can we improve it?

Join the conversation

2 Responses

  1. I just got a dog and she went into heat around August 2nd, she has an appointment to be spade on August 27th. She was a stray and had obviously had a litter of puppies before, the vet thinks she is about 2 years old. Can she be spade while she is in heat?

    1. Hello Julie,

      thank you for your question. It is great to hear that you were willing to adopt a stray dog and gave her a new chance on life and home. As to your question – it is possible to get your dog spayed when she is in heat, however, it is not recommended because of possible complications. It would be safer to wait few weeks for the heat to end, and proceed to spaying after that.

      Hope this helps.

Leave a Reply

You’re very welcome to leave a comment or question. Please know that all comments must meet our community guidelines, and your email address will NOT be published. Let’s have a positive and constructive conversation.


Talk With A Vet Online

Peace of mind,
anywhere, anytime

Affordable vet advice

Ask Dr. Paola- Help! My Dog’s Sleeping Habits Have Changed! (May 18, 2026)

Welcome to our “Ask Dr. Paola” series, where every Monday we bring expert advice straight from Dr. Paola Cuevas (MVZ) to help our...

The Crate Setup Most Dog Owners Get Wrong (And How To Fix It!)

Most people assume that if their dog hates the crate, the crate is the problem. So they try a bigger one, a different...

1,500 Beagles Rescued from Wisconsin Lab Farm – Here’s Where They’re Going

You may remember that a few weeks ago, we reported on a tense situation at Ridglan Farms, Wisconsin, a facility infamous for housing...

Dogster’s Weekly Photo Contest Winners: Window Watchers (May 11, 2026)

Every week our team gets the privilege of sorting through our readers photos to choose what dogs will win this weeks contest! See...

More related

500+ Popular & Unique Boykin Spaniel Names: Ideas For Curly Posh Dogs

Choosing a name for your dog can feel like an overwhelming task. When you start looking into names, you’ll quickly realize that there...

Dark Golden Retriever: Info, Pictures, Origin & History

Golden Retrievers are one of the most beloved dog breeds in the world. Famed for their loyalty, gentleness, and, not to mention, beauty,...

Why Your Dogs Only Play When You’re Around? 5 Likely Reasons

Dogs love to play and roll around with their canine companions. What’s interesting is that dogs play more when their owner is paying...

What Are the Canine Good Citizen (CGC) Requirements? Test Tips & FAQ

The Canine Good Citizen program is a certification program offered by the American Kennel Club. It tests a dog’s basic good manners and...

Keep reading

Can Dogs Eat Carne Asada? Vet Reviewed Facts & FAQ

You may be familiar with the phrase “puppy dog eyes.” That is why saying “no” to a dog is next to impossible when they want something, whether they want to play, get up on the couch with you, or eat...

Can Dogs Eat_carne asada

Can Dogs Eat Chayote? Vet-Verified Facts & FAQ

Chayote (or mirliton/choko) is a fruit that belongs to the gourd family and was first cultivated in Mexico and Honduras. These fruits are a great snack for dogs; they can eat them without any issues. Chayote is nutritious and versatile,...

Can Dogs Eat_chayote

Can Dogs Eat Capers? Vet-Reviewed Nutrition Facts & FAQ

You love your dog, so you want to give them treats every now and again, and sometimes those treats are your own food. A lot of the time, depending on the food, this is (mostly) fine for your pet. But...

Can Dogs Eat Capers

How to Start a Dog Food Business: 10 Tips & Tricks

Given how important nutrition is to pet health, starting your own dog food business can be an interesting and even lucrative idea. Indeed, according to IBISWorld, the pet food industry brings in $27 billion a year, and it is growing...

Pet Food Packets At Store

Weruva Dog Food Review 2026: Pros, Cons, Recalls, and Guide

Review Summary Weruva may sound like an odd name for a pet food brand, but the name was actually inspired by the creators’ cats: Webster, Rudi, and Vanessa. The first syllables of each name were taken and blended to create...

Dogster_Weruva Dog Food Review

Can Dogs Eat Frosted Flakes? Vet-Verified Facts & Nutrition Guide

While Frosted Flakes are a popular breakfast food for both children and adults, they’re not so great for dogs. Frosted Flakes don’t add any nutritional value to a dog’s diet, and the added sugar can lead to health complications if...

Can Dogs Eat Frosted Flakes

6 Best Dog Food Mats in 2026 – Reviews & Top Picks

While we all love our furry pets, every pet parent knows that when dogs eat and drink, they tend to get food and water all over your lovely clean kitchen floor. Luckily, dog food mats stop that from happening and...

dog food bowl in a food mat

Can Dogs Eat Smoked Salmon? Vet-Approved Benefits & Risks

If your dog tends to eat fish, you may wonder if human delicacies, such as smoked salmon, are suitable for your furry friend. Salmon has many benefits and is an excellent source of protein and omega-3 fatty acids for humans...

Can Dogs Eat Smoked Salmon

Love Dogs? So Do We! Join the Dogster Community

Stay informed with expert pet care insights delivered straight to your inbox! Discover professional guidance on animal behavior, feeding tips, trusted product picks, and much more.




Sign up for the Dogster Email Newsletter