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When Do Boxers Go Into Heat: ALL About Boxer Heat Cycles

There are many great questions owners have on their boxer’s heat cycle. When will your boxer experience their first heat? What are the signs to look out for? And how will this change their behavior?

This article contains everything an owner should know, let’s get started!


When Do Boxer Dogs Go Into Heat?

Most boxers go into their first heat between 6 and 12 months of age, although some may fall outside this range. Few boxers may go into heat as early as 4 months, and others as late as 18 months.

The most important thing to take away from this is that heat cycles are not very predictable in the beginning.

I have spoken to many owners who say their boxer entered heat around 8 months, others at 4, and a few at 16 months.

There is no “correct” age for your boxer to enter heat, and it doesn’t matter if she’s early, average or late. The best to do is learn the signs she’s entering heat, and be prepared. Let’s get into that now!

Signs Your Boxer Is Going Into Heat

The next most frequently asked question is what are the signs to look out for that indicate the heat is coming!

Signs your boxer is entering heat:

● Swollen vulva
● Blood spots or bleeding
● Discharge of any consistency
● Paying extra attention to her genital area
● Change in temperament (moody swings, neediness, aloofness)
● Change in eating habits
● Reduced energy
● Increased urination
● Holding her tail differently

Important note: You may not notice ALL of these signs happening. Your boxer might exhibit some signs more than others, so it’s crucial not to get fixated on spotting one single sign, as it could be any one of them.

Typically, the most common signs are a change in temperament, swollen vulva, blood spots, discharge, and paying more attention to her genitals.

As long as you know what’s “normal” for your boxer, it will be easy to spot when anything changes.

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How Often Do Boxers Go Into Heat?

Most boxers have TWO heat cycles per year, but it can be a while before they become regular and predictable. It usually takes 2 or 3 heat cycles before owners can predict when the next one happens.

Don’t worry too much about timing in the early stages. Even after your boxer has the first one, it doesn’t necessarily mean the next one will happen in exactly 6 months.

How Long Are Boxers In Heat For?

Most boxers will be in heat for around 21 days (3 weeks), give or take a few days. The first 7-10 days is the proestrus stage and your boxer will not be fertile, the next 7-10 days is when your boxer will be fertile. After this, her body will slowly return to normal over the course of another week.

The two most important stages to be aware of are the proestrus stage and the estrus stage, which take up the majority of the 3 weeks. After this, her body will be returning to normal if she hasn’t conceived.

Let’s discuss the stages in full detail below.

Popular article: Why do boxers have their tails docked? Full explanation

Boxer Heat Cycle Stages

Every heat cycle is comprised of 4 individual stages. While it helps to know the difference between all four stages, the first two are the most important. We’ll discuss them below.

1. Proestrus Stage

The first stage of the heat cycle is called the proestrus stage. This lasts for around the first 7-10 days. The CRUCIAL thing to know about this stage is that your boxer is NOT fertile, and she will not accept males. In fact, she will likely be very aggressive towards males in during proestrus.

Signs of Proestrus:
● Change in temperament
● Swollen vulva
● Bleeding/bloodspots/discharge
● Tail tucking
● Paying more attention to her genitals

2. Estrus Stage

The Estrus stage is perhaps the most significant stage because now your boxer IS fertile and capable of conceiving. It’s not uncommon for females in Estrus to take it upon themselves to find a partner (more on this later). The Estrus stage usually lasts for 7-10 days following the proestrus stage.

Signs of Estrus:
● Holding tail to the side
● Increased urination
● Discharge might slow down or change color
● Will accept males and act flirtatiously
● Will be more aloof and aggressive towards other female dogs

3. Diestrus Stage

The third stage is called Diestrus. If your boxer has not been impregnated, her body will begin the process of returning back to normal. If she has conceived, then this is the stage she remains in for 60-70 days until giving birth.

Signs of Diestrus:
● Discharge will slow down before stopping completely
● Volva will return back to normal size

4. Anestrus Stage

The Anestrus stage is considered the resting stage.

Your boxer’s body will be completely back to normal, and she’ll remain like this until the next heat cycle begins.

What To Expect When Your Boxer Goes Into Heat?

Something that many owners worry about is how to care for their boxer when they go into heat. What should you expect? How will your boxer handle it? and do you need to do anything specifically? Let’s run through it.

Change in behavior and temperament

The first thing to keep in mind is that her behavior and temperament will likely change. This means she’s going to seem “off” or very “different” from her usual bouncy self.

This can be quite worrying for owners, especially during the first one, but just know this is a normal reaction.

She might appear less enthusiastic, tired, extra needy, clingy, more aloof, or irritable. From good to bad, it’s all possible (and normal).

Whatever the change is, just be sure to go with it. It can be very hard to gauge exactly how she’s feeling and what she wants, but as long as you are there, it’s okay to let her be the one to decide if she wants extra attention or not.

It’s crucial to inform all house members (especially kids!) about this change in behavior. Everyone needs to be on the same page, giving her space when she wants it, and support when she wants.

She needs to be supervised outside

As soon as your boxer enters the first stage (proestrus) it’s important to supervise her outside at all times.

Her scent will travel far and male dogs will be attracted to her right away. You want to avoid all close encounters with male dogs as your boxer will likely react aggressively.

I always recommend using a long leash, even in your own yard. This is particularly crucial when your boxer is in the estrus stage and fertile. She’ll be looking for a partner and may even take it upon herself to escape the yard to find one. Make no mistake, this happens often!

Exercising your boxer in the yard is the safer option while she’s in heat. It’s possible to visit the dog park, but in my opinion, it’s dramatically increasing the chances of a negative interaction that could end badly. The yard will suffice for three weeks IMO.

Extra cleaning will be necessary

Blood spots and discharge are a part of every heat cycle, we can’t stop it from happening, so all we can do is be ready for it.

It helps to keep your boxer in fewer rooms of the house while she’s in heat. This will reduce the amount of blood and discharge in different areas and will make cleaning easier.

If you aren’t putting towels down on her bed, then her bed will need to be washed almost every other day. This is to reduce the amount of bacteria build-up and to keep her area as hygienic as possible.

Be sure to grab some pet-friendly cleaning products and remind yourself this is only a temporary blitz of mess! Stay sane! lol

Create a calm environment for her

As well as being there for her, it helps to make her immediate environment as calm and relaxing as possible.

She’ll likely be more tired, irritable, and some boxers may experience low-level pain while in heat. So having a place to lay down in peace and quiet is a small but crucial thing to ensure.

Little things like shutting the windows to reduce external noise, making her bed more comfortable with towels, and even playing classical music (yep, classic music is said to be very relaxing for most dogs!).

There’s no right or wrong way to do this, just try your best to create a calm environment for her.

What Age Can Boxers Have Puppies/Breed?

There’s two answers to this, the technical answer, and a more responsible answer that takes into account the health and safety of the mother and future litter.

Technically, boxers can have puppies and be bred from their first heat cycle, whenever that is. For some, this may be as early as 4 months old.

This, however, is not recommended, even if your boxer has her first heat later than this.

It’s recommended that a female boxer has 3 or 4 heat cycles before being bred. By this time, she should be at least 2 years old. This gives her time to mature mentally and physically before putting her through such a strenuous event.

By waiting, you also gain more time to check for potential health issues. Some health problems don’t show themselves until around 1-2 years old.

For those that breed early, there’s a strong chance of passing down health issues to the offspring. This is unfair and does not fall in line with responsible breeding.

In addition to this, by waiting a little longer, the mother will be more mature, sensible, and capable of raising a litter. For those that are bred very young, it often causes excess stress and behavioral issues further down the line.

How Many Puppies Do Boxers Normally Have?

Boxers normally have between 5-7 puppies in a litter, although this can vary drastically. Some boxers may only have 3 or 4 puppies and others could even have up to 10 puppies in a single litter.

There’s no real way to gauge litter size beforehand.

Although many think the large the dog, the large the litter size, this doesn’t always work out to be the case.

Thank you for reading!

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Before making any decisions that could affect the health and/or safety of your dog, you should always consult a trained veterinarian in your local area. Even though this content may have been written/reviewed by a trained veterinarian, our advice to you is to always consult your own local veterinarian in person. Please read our full dislcaimer if you have any questions.