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

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

Apricot Labradoodle: Info, Pictures, Origin & More

Labradoodles have gained popularity over the years, and it’s no wonder why! According to the AKC, their Labrador Retriever is one of the...

What to Put in a Dog First Aid Kit: 20 Vet-Approved Essential Items

Whether you’re hanging out at home with your dog or taking them for a walk, an emergency situation is always a possibility, so...

My Dog Licked Triple Antibiotic Ointment! Vet-Approved Advice

Triple Antibiotic Ointment (TAO) is a combination medication of bacitracin, neomycin, and polymyxin B. These antibiotics treat minor scrapes, skin infections, or burns....

Social Media for Dog Owners in 2025: 5 Apps for Our Furry Friends

Social media has many platforms for sharing pictures and making new friends. Your dog can even take part, as adorable pet pictures are...

More related

Are Dogs Allowed in Safeway? 2025 In-Store Pet Policy

Dogs are not allowed in Safeway stores, except for service dogs when they accompany visitors with disabilities. Many laws around the country control...

How to Keep Ants Out of Dog Food: 10 Easy & Effective Tips

Do you have a problem with ants getting into your dog food? If so, you’re not alone. Ants are persistent and can find...

Male vs Female Rhodesian Ridgeback: What’s The Difference (With Pictures)

The Rhodesian Ridgeback dog breed is a loyal and assertive dog that is always willing to please its owners. This medium to large...

6 Common Health Problems in Pugs (Vet Answer)

In the veterinary world, we have seen an uptick in what are referred to as brachycephalic breeds. These are more lovingly known as...

Keep reading

10 Common Sources of Fats for Dogs: Canine Nutrition & Health

Just like people, dogs need fat in their diet. Dogs need quite a bit of fat. In the wild, dogs would be eating most prey animals, which are high in protein and fat. In a domestic setting, they need similar...

dog drinking in the water bowl

Where Is Wellness Dog Food Made? Manufacturing Location & Facts

Wellness pet foods are among the most popular trendy health foods on the market right now that you can get for your dog. Their foods are well-loved by dog parents who find their affordable foods perfect for their pets’ needs....

Wellness CORE Senior Dry Dog Food

Can Dogs Eat Cherry Tomatoes? Vet Approved Nutrition Facts & Advice

Cherry tomatoes are just about the perfect human snack. The small bright red treats are just the right size to pop in your mouth for a mid-afternoon pick-me-up, and they’re great when sliced in half and added to salads or...

Can Dogs Eat_cherry tomatoes

Can Dogs Eat Durian? Vet-Verified Nutrition Facts & Safer Alternatives

The durian fruit has gained a lot of attention for its pungent aroma rather than its taste or any health benefits. The fruit comes encased in a prickly shell, and “the king of fruits” has a smell that is described...

Dogster-Can-Dogs-Eat-Durian

The Farmer’s Dog vs Spot & Tango: Our 2025 In-Depth Comparison

It’s easy to get lost when venturing through the pet food jungle. With our dogs being part of the family, we want only the best for them when it comes to food. Trying to find the best brands, tasty recipes,...

Dogster_Dog Food The Farmer_s Dog VS Spot & Tango

10 Best Canned Dog Foods for Picky Eaters in 2025: Reviews & Top Picks

While it can be a mystery as to why some dogs are picky, finding dog food that a picky dog enjoys can feel like an even greater mystery to solve. Many dog owners have found solutions with meal toppers and...

shih tzu dog getting wet food from owner at kitchen

7 Best Dog Foods for Hip Dysplasia in 2025 – Reviews & Top Picks

Dogs love to run and play, but if your dog has mobility issues like hip dysplasia, the joint pain can prevent these fun activities. Hip dysplasia is an abnormal formation of the hip socket that can cause dysfunction and pain,...

close up of a dog eating from the bowl

Can Dogs Eat Bratwurst? Vet-Verified Facts & FAQ

Bratwurst is a tasty sausage that goes hand-in-hand with backyard cookouts. They are easy to throw on the grill, and you can eat them easily while hanging outside and engaging in summertime activities. For those who have dogs, you may...

Can Dogs Eat Bratwurst