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When Do Shih Tzus Go Into Heat: All You Need to Know

Understanding when your Shih Tzu enters heat can be a bit puzzling, and it’s no surprise that many pet owners have numerous questions about this subject.

This article aims to clarify everything and address the most frequently asked questions regarding Shih Tzus and their heat cycles.

In this article, you’ll learn about:

  • When Shih Tzus experience heat
  • The indicators to watch for
  • The duration of heat for Shih Tzus
  • The frequency of heat cycles
  • The four distinct phases of each heat cycle
  • Tips for caring for your Shih Tzu during heat
  • Breeding inquiries

Let’s dive in!

When Do Shih Tzus Have Their First Heat?

In general, Shih Tzus will undergo their first heat between 4-8 months of age. Nonetheless, some Shih Tzus might enter heat earlier or later than this, which remains entirely normal.

For a few, it could occur as early as 4 months, while for others, it might be as late as 8 months or more.

The essential point to remember is that there’s no fixed schedule!

While the 4-8 month range is when a majority of Shih Tzus experience their first heat, it doesn’t apply to every single one.

There are instances of Shih Tzus going through their first heat at just 4 months old, and other cases where they don’t have their first heat until they’re 8 months of even later

This naturally leads us to the next part of the discussion, the signals to be on the lookout for!

11 Signs That Your Shih Tzu Is Entering Heat

What are the indicators to keep an eye on that suggest your Shih Tzu is entering heat? This is undeniably the next most frequent question. So let’s address them!

Signs your Shih Tzu is entering heat:

● Bleeding & blood spots
● Blood-tinged discharge
● Enlarged vulva
● Increased licking of the genital area
● More frequent urination
● Greater focus on her genital area in general
● Aggression towards male dogs
● Alteration in temperament
● Shift in energy levels
● Change in appetite
● Carrying her tail differently

As with timing, the signs your Shih Tzu displays can vary, and some individuals will show certain symptoms more noticeably than others. Some Shih Tzus might bleed considerably, while others may not seem to bleed at all!

Nonetheless, most females WILL exhibit at least one or two of the most common primary signs: bleeding, discharge, a swollen vulva, or increased attention to her genital area.

By closely monitoring your Shih Tzu on a daily basis, you’ll be able to spot any deviations from her normal behavior more quickly. And that’s the key!

How Long Do Shih Tzus Stay In Heat?

Shih Tzus typically remain in heat for around 3 weeks (21 days), with a margin of a few days either way.

During the initial 8-10 days, your Shih Tzu won’t be interested in mating, while in the last 8-10 days, she will be receptive and able to become pregnant.

Although there are technically four stages (explained below), the first two are the most significant and constitute the period when we consider a dog to be in heat.

More information on heat cycle stages coming up!

How Often Do Shih Tzus Go Into Heat?

Most Shih Tzus will experience 2-3 heat cycles per year. Every 4-8 months in normal for Shih Tzus.

Some may have only have two heat cycles per year, while other will average about three. Either way this is completely normal.

In general, the smaller the dog the more frequent their heat cycles are. Giant breeds may only have one heat cycle per year, but Shih Tzus, on the other hand experience them at a much greater frequency.

Shih Tzu Heat Cycle Stages

The Four Phases of Your Shih Tzu’s Heat Cycle

Your Shih Tzu’s heat cycle consists of four distinct stages. Each stage represents a different aspect of the cycle, so it’s vital to comprehend what each one involves.

Your Shih Tzu will show different signs based on the current stage of her cycle.

1. Proestrus Stage

The first stage, known as the proestrus stage, generally lasts 8-10 days. During this time, your Shih Tzu’s body readies itself for mating and pregnancy. However, she will NOT be interested in mating during the proestrus stage, which often results in aggression towards male dogs to keep them away.

For most Shih Tzus, the proestrus stage lasts between 8-10 days, but it can vary by a few days either way.

➡️ Signs of the proestrus stage:

● Swollen vulva
● Tail tucking
● Bleeding
● Discharge
● Genital area licking
● Aggression towards male dogs

2. Estrus Stage

The next stage, called the estrus stage, is when your Shih Tzu becomes fertile and ready to mate. She will welcome male dogs and probably keep her tail to the side when they approach.

During this phase, she may also urinate more frequently and exhibit aggression towards female dogs.

In most cases, the estrus stage lasts between 8-10 days for Shih Tzus, though this duration may vary slightly.

➡️ Signs of the estrus stage:

● More frequent urination
● Tail held to the side
● Receptiveness to male dogs
● Possible aggression towards female dogs
● Changes in discharge color, consistency, or volume

3. Diestrus Stage

Following the estrus stage is the diestrus stage, during which your Shih Tzu’s body reverts to its normal state. If she hasn’t conceived, this stage will persist for approximately 7 days after the estrus stage.

If she is pregnant, however, this stage will continue throughout the 60-70 day gestation period until she gives birth.

➡️ Signs of the diestrus stage:

● Vulva shrinking to its normal size within 7-10 days
● Discharge gradually diminishing until it ceases entirely

4. Anestrus Stage

The anestrus stage serves as the final resting phase.

In short, your Shih Tzu remains in this stage until her heat cycle recommences with the proestrus stage.

Tips for Taking Care of Your Shih Tzu in Heat

Being prepared for your Shih Tzu’s heat cycle primarily involves recognizing the signs (as mentioned above) so you can be ready when it happens.

Here are some of the top tips to help you care for your Shih Tzu when she’s approaching and experiencing her heat cycle.

Avoid unsupervised outdoor time

Surprisingly, male dogs can detect your Shih Tzu entering heat from miles away, which may encourage them to approach her. Some males will go to great lengths to enter your yard.

Also, during the estrus stage, your Shih Tzu might try to escape to find a mate. Always supervise her when she’s outside, and ideally, use a leash even for bathroom breaks.

Always use a leash during heat

Whether you’re going for a walk or letting her outside for a bathroom break, using a leash is essential. When your Shih Tzu is in heat, she may be more likely to run off or escape. This occurs more often than owners realize, so don’t take the risk.

Be understanding of her mood changes

Shih Tzus will react differently during heat. Some may become extra clingy, while others may prefer to stay in their bed. Remember, these behaviors are temporary and will pass.

She may also exhibit mood swings and changes in temperament, so ensure your family understands that this is normal. Offer comfort when she needs it and give her space when she wants it.

Schedule a vet check-up

To be cautious, consider taking your Shih Tzu to the veterinarian for an assessment to confirm that everything is okay.

Don’t hesitate to consult your veterinarian, even if nothing seems amiss.

There are potential health issues that can occur after the heat cycle, so contacting your veterinarian as a precautionary measure is advisable.

Be prepared for extra mess

Expect some mess from bleeding, discharge, and increased urination. Be ready with extra towels to protect your floors and other areas your Shih Tzu frequents.

Some owners confine their Shih Tzu to a single room due to the mess, but if you prepare adequately, your dog can continue to enjoy her usual space.

Maintain a clean sleeping area

Her bed and sleeping area may become messy, so try to keep it as clean as possible. This might involve washing the bed or swapping it out daily to minimize bacteria buildup.

Consider hygiene pants

Hygiene pants or “doggy diapers” can help manage the mess and prevent unwanted pregnancies during walks. Some dogs adapt well to these pants, while others may dislike them. However, they’re worth trying. Most have replaceable pads inside.

When Can Shih Tzus Begin Breeding?

Shih Tzus should not start breeding until they’ve experienced 3-4 heat cycles.

This waiting period allows them to mature physically and mentally before undergoing the biologically demanding process of breeding.

While it’s true that a Shih Tzu could technically become pregnant during her first heat cycle and give birth to a litter of puppies 50-60 days later, this is not advisable.

So, there are two different answers: the technical answer, as mentioned above, and the recommended approach, which considers your Shih Tzu’s health and well-being.

Many Shih Tzus will have their first heat cycle between 4-8 months of age, but they are still considered puppies at this stage.

Breeding Shih Tzus at this young age can negatively impact their mental and behavioral health and increase the likelihood of passing on health issues to their offspring.

At this early age months old, some potential illnesses or diseases may not yet be apparent. In an effort to breed responsibly, it’s important to only breed healthy females and males without any known health issues.

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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.