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When Do Chihuahuas Go Into Heat: Full Heat Guide & FAQs

Knowing when your chihuahua will have her first heat isn’t so straightforward.

This important topic has many questions and answers, and it’s best for owners to be fully prepared of what’s to come. This article has everything you need to know!

The quick answer: Most Chihuahuas get their first heat between 6 and 10 months of age. But keep in mind this timeframe varies as some may enter heat a little earlier or even later, up to 16 months.

When Will Your Chihuahua Go Into Heat?

chihuahua heat cycle

The most common age for chihuahuas to experience their first heat cycle is between 6 and 10 months of age.

However, this timeframe isn’t fixed. Some Chihuahuas may experience their heat cycle as early as 4 months, and others as late as 16 months.

There isn’t one answer that fits all with this question. So, this is why owners must know all the signs and be observative from the four months mark.

How Often Do Chihuahuas Go Into Heat?

Most Chihuahuas experience TWO heat cycles PER YEAR. This is the standard amount of heat cycles that nearly all chihuahuas will have.

Keep in mind it can take about three heat cycles in the beginning to establish a stable frequency and pattern. Before their third heat cycle, the timings of each one can be a little unpredictable.

Signs Your Chihuahua Is Going Into Heat:

So what are the signs that indicate your Chihuahua is going into heat? This is crucial to know in the early stages.

7 KEY Signs your Chihuahua is entering heat:

  • Swelling of the vulva
  • Blood spots or discharge
  • Tail tucking
  • Extra attention to her genital area
  • Change in appetite
  • Change in behavior (mood swings)
  • Aggression towards male dogs

Please remember that not all of these signs may happen together or in order above. Some of them may not happen at all.

As a new owner preparing for their pup to enter heat, be on the lookout for ANY of the signs.

Personal experience: For many dogs, blood spots are one of the first signs most owners notice, but with two of mine, blood spots or discharge were hardly noticeable.

What To Expect When Your Chihuahua Goes Into Heat

Most owners are worried about what will happen to their chihuahua during heat… How will she change? Will she be hard to manage? and so fourth…

Let’s explain exactly how most Chihuahuas react during their first heat cycle.

1. Behavior changes

When a chihuahua is in heat, you may notice several behavioral changes.

These may include decreased activity and increased fatigue, appearing unwell, and being more clingy. These are all completely normal during heat.

It’s also common for your chihuahua to be whiney, uncomfortable, and unhappy, which can cause you to feel worried and want to do more to help.

It’s essential to be there for your chihuahua and provide support despite her unpredictable behavior.

2. Appetite changes

It’s completely normal and to be expected that your Chihuahua’s appetite may change. For most, it decreases their appetite, but for some, it increases.

Be ready to tackle food refusal by making their food more appealing. You could add in wet dog food to the mix, pour a little meat broth over the food, or use dog food toppings.

Just ensure that your Chihuahua does actually eat something eventually. If she goes more than 24 hours without eating anything, please contact your veterinarian.

3. Bleeding

During heat, a chihuahua’s bleeding will typically increase and last for approximately 2-3 weeks.

It’s a good idea to have an ample supply of old bath towels and liners on hand to replace them frequently and keep the area as clean as possible.

Some owners also suggest using nappies or male underwear with a hole for the tail, which will also need to be replaced multiple times per day.

4. Outside safety

This is an important one! Taking your chihuahua outside is a whole different ballgame while she’s in heat.

Male dogs will smell her scent from miles away, and all will be interested in her. During the first stage of her heat cycle she’ll only show aggression to male dogs, so it’s crucial she stays far away from them.

During the fertile stage, this aggression will switch towards the females. All in all, it’s crucial to limit all interactions with other dogs while she’s in heat.

This means keeping her on the leash and only going to the dog park during the quietest times.

In our opinion, it’s best to simply exercise your chihuahua at home for these weeks to keep her safe.

5. Know that all these changes are temporary

It can be overwhelming dealing with all these weird changes as an owner. It’s definitely worrying see your beloved pup go through such mood swings and character changes, but just know that it’s normal and temporary.

Sometimes your chihuahua will want extra attention and other times she won’t want anything to do with anyone! It’s just how it is.

It’s important to explain this to everyone living in the household. Provide unconditional support, and roll with her changing mood and behaviors.

During this time, expect some level of disobedience and bad behavior. Yes, it’s still important to correct negative behavior, just don’t go too hard on her.

Chihuahua Heat Cycle Stages: Explained

To really understand what’s happening with your Chihuahua during heat, it’s necessary to know the four stages of the heat cycle.

The first two stages of the heat cycle are by far the most important. I’ll explain below.

1. Proestrust

The first stage of your Chihuahuas heat cycle is called Proestrus.

During this stage, her body is preparing her to mate, yet she will NOT be fertile during this stage. This is crucial to remember, and is why she’ll be aggressive towards males.

  • Proestrus lasts 7-10 days
  • Swollen vulva
  • Blood spots
  • Tail tucking
  • Aggression towards males
  • Unusual changes in behavior

2. Estrus

The second stage of each heat cycle, and arguably the most notable, is called Estrus.

This is now when your Chihuahua is fertile, capable of mating, and will even take it upon herself to seek out an intact male. In most cases, a female in Estrus will accept almost any intact male dog.

Her discharge will likely become quite watery at this point. This means she’s at her most fertile point.

  • Estrus lasts another 7-10 days
  • She’ll be capable of conceiving and accepting of male dogs
  • Aggression towards female dogs is normal
  • Watery discharge
  • Unpredictable mood swings

3. Diestrus

The third stage of the heat cycle is called Diestrus, and is the stage your Chihuahua would remain at IF she were to get pregnant.

If successful mating did not happen, then her body will return back to normal in 7-10 days during Diestrus.

4. Anestrus

The fourth stage of the heat cycle is the resting stage. Nothing happens during Anestrus and is what your Chihuahua remains in until her next heat cycle begins.

How To Help Your Chihuahua During Heat

Let’s run through the best ways to help your chihuahua during heat. This should help alleviate some worries and concerns.

1. Limit her space

Instead of having free roam over the whole house, limit her living area to one or two rooms during heat.

This will limit mess and keep it easier to monitor her behavior and how shes’ doing.

2. Monitor her outside

It’s best to exercise her at home for these weeks, the risks outside are too significant. Still, it’s advised to monitor your chihuahua even in your own backyard.

It’s common for eager males to try gaining access to the yard, and during Estrus, it’s common for female dogs to escape their own yard in order to find a mate.

Some owners may even keep their chihuahua on a leash when in their yard.

3. Be ready for food refusal

It’s crucial your chihuahua keeps eating, yet her appetite will most likely change.

If she starts showing signs of food refusal, it’s essential to have a plan in place.

You can make their food more appealing by either adding in wet dog food, meat broth, or food toppers.

If she refuses all food for 24 hours it’s important to consult with your veterinarian.

4. Wash her bed area

During heat, her bed will be a breeding ground for bacteria, especially with the blood and discharge that happens.

For basic hygiene purposes and to keep your pup healthy, it’s necessary to wash her bed every other day to limit bacteria buildup.

It’s wise to put down at least a couple of old towels over her bed for easy cleaning.

5. Consider scheduling a vet appointment

Although it’s extremely rare, there are a few known health complications that could potentially happen after a dogs first heat cycle.

It’s absolutely not necessary and many people don’t do this, but to be on the safe side you could schedule her bi-yearly vet check up starting after her heat.

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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.