If you are a Shih Tzu owner, you should already know by now what we’re dealing with when we talk about ‘heat cycle’ or a female dog coming to heat. While most female Shih Tzu owners know what they have to deal with if they have an unspayed female Tzu, it also has an effect on male Shih Tzus. In this article, we’ll include some hints and tips on how heat cycles can affect both male and female Shih Tzus and what you can do to cope up with it.

The term ‘Heat’ is a term used to describe a female dog’s menstrual cycle. It is around this time that there will be some bloody discharge on her uvula and it is at this time that a female dog can become pregnant. This is also called as ‘heat cycle’, ‘heat season’, ‘entering into season’, and ‘estrus cycles’ being on or in heat.


Shih Tzu puppies eventually grow mature and changes happen to both their physical appearance, habits and even their reproductive organs. The maturation of sexual organs happen in both male and female Shih Tzus and when this time comes, they are ready for reproduction during the heat cycle.

Heat is the stage in which a Shih Tzu female is prepared for reproduction and it can have an effect on male dogs. With the arrival of a heat cycle, your Shih Tzu can experience different changes partly due to the hormonal load and it is important for you to recognize these changes so you’ll know how to respond to it and make the cycle a smooth transition for your Shih Tzu.

How Long is the Heat Cycle?

Small breeds like the Shih Tzu usually have their cycle earlier than the other breeds. This starts between the age of 4 and 7 months old which is a surprise to a lot of owners because around this time, the Shih Tzu is still considered a puppy.

The approximate duration of the heat cycle is usually between 2 and 4 weeks (or 23 days) and it usually happens twice a year. We recommend that you write the dates of the beginning and end of your Shih Tzu heat cycle so you can monitor its pattern. Although you can’t really point out the exact date of their next heat cycle, you can use this to track anomalies that need to be addressed to a veterinarian.

If you have a female Shih Tzu that has not been spayed and hasn’t had her first heat after a year, you’ll want to check with a Veterinarian to make sure that she does not have any underlying medical issues.

The Four Stages of  the Heat Cycle

During the heat cycle, a Shih Tzu goes through different stages stated below:

  • STAGE 1: The vulva becomes inflamed (for female Shih Tzus) for about 7 to 10 days and small amounts of blood appear. In this phase, the female dog in heat usually rejects any male dog trying to approach her.
  • STAGE 2: In 5 to 15 days, the female dog lets the male dogs smell their vulva, a gesture that means the ovulation has begun. During this stage, the bloody discharge stops but the vulva will remain inflamed.
  • STAGE 3: This lasts for about 60 days. In case of pregnancy, this will be the longest stage which can last for about 110 to 140 days which is the period of pregnancy and lactation for Shih Tzus.
  • STAGE 4: This is considered as a ‘sexual rest’. It’s not easy to estimate its duration since it’s the period that lasts from the end of stage 3 to the beginning of the next heat cycle.

In order for a Shih Tzu to become pregnant, mating must be carried out between 8 to 15 days of each cycle which are the days of ovulation.

It’s important to know that even senior dogs can still come into heat; menopause does not happen in dogs like it does with humans. This being said, the discharge observed in senior dogs will be lighter than when she was younger and the cycles may be further apart. This is another reason why spaying is recommended because even senior dogs can still become pregnant. The older a dog is when they become pregnant, the more stress there is on the body and the greater the risk of pregnancy complications.

Common Signs of a Shih Tzu Being in Heat

shih tzu heat cycle

You might be a new owner or have a Shih Tzu rescue that has not been spayed so here are some common signs that might help you out:

  • Her vulva might enlarge 2 or 3 more times its normal size.
  • There will be a discharge that varies from light to moderate.
  • The colour of the discharge can be from whitish-pink to red. It’s normal for the colour to change during the cycle.
  • Male dogs will be interested in your female Shih Tzu, even stray dogs may hang out around your yard, garden or doors. Unneutered male dogs will be able to detect female dogs in heat – they can literally smell them up to 3 miles away. With this in mind, we recommend that you keep your female dog in heat inside the house as much as possible.
  • Mild mood changes will be observed. Some female dogs will have nesting tendencies which means that they will be moving objects to their bed or resting spot. Others will be withdrawn or quiet. Look for unusual behavioural changes.
  • Your female Shih Tzu may present herself to male dogs which is usually done by flagging a male. This is when she moves her tail to the side (like a flag) and presents her rump.


When your Shih Tzu bitch is in heat, you will notice different changes to their body and behaviour such as the following:

  • Being anxious and nervous
  • Frequent urination
  • Inflamed vulva
  • Increased breast size
  • Bleeding
  • Less affectionate towards owners
  • Becoming more playful and friendly with male dogs

Male Shih Tzus spend their heat cycle differently from Female Shih Tzus. Their heat cycle begins as soon as they smell pheromones in the air that a female gives off when they are in heat. For a male, the smell of female pheromones becomes irresistible, hypnotizing, and extremely intoxicating and it will be this smell that pushes him to look for the female dog which is why it’s common to see a female dog walking with a bunch of male dogs behind her waiting for her acceptance.

When it comes to a heat cycle, both male and female undergo changes such as the following:

Frustration and Aggressiveness

When the male dog enters into the heat cycle, the production of testosterone (male hormone) is triggered which increases the production of another lesser-known hormone which is cortisol.

Cortisol chemicals are the main cause of stress, irritability, frustration, and aggressiveness. This is the main reason why many dogs live in continuous stress and it can also lead to other types of psychological problems. On the other hand, a male dog that has detected a female in heat nearby will not allow other males around her so usually dogs with an affectionate character can become aggressive toward other dogs.


If a female dog rejects a male dog, the male dog can suffer from depression due to the simple fact that they thought the smell from the female dog would result in the opportunity to mate and breed. This depression can manifest itself with behaviours such as a decrease in appetite, crying, fatigue, or even howling.

Being Reckless

Females in heat urinate more often so male dogs will tend to follow the smell that they left. So without thinking about their owners, they will try to find the source of that smell and will even try to cross dangerous streets in their pursuit. If you notice your male dog being fixated more than usual on smelling, exercise some caution on walks. They can bolt and be very determined in getting to an on heat female.

Improper Marking

A male dog that smells pheromones in the air will feel a great need to leave his mark in different areas which can cause problems especially at home because he will leave his scent anyhere he feels the need to. That can also include places inside the home.

Confusion & Stress

This is marked by different states of stress. Your dog may even ignore you and be distracted or confused. This is a behaviour that usually can lead us to think that our dog has become rebellious when it’s really a jealous reaction to other male dogs around them.


taking care of shih tzu in heat cycle

Although Shih Tzu females might display very small amounts of discharge from the vulva, it’s important to keep your dog and your home clean. You can put on a diaper on her and even clothes over it to protect your floors and furnishings from the discharge. Since she will become the center of attention to male dogs, you have to make sure that she’s safe.

Although it’s best to keep her inside the house, it’s not always going to be possible. If you need to take her out, make sure that you use a short leash because male dogs can smell her and will be very determined in trying to reach her. There is nothing that drives a dog more than the chance to reproduce.

Tips To Prevent Your Female Shih Tzu From Being Chased By Males

  • Do not leave your Shih alone when she’s ovulating as there’s a possibility that she might escape looking for a male dog to mate with. They can be quite creative in planning their escape!
  • If you have a male Shih Tzu, we recommend that you keep them apart from female dogs in heat since the pheromones being produced can change their character drastically as their base needs take over.
  • Be careful with open doors and windows as your Shih Tzu may want to escape during the heat cycle and she will be faster than you might expect.
  • Assign a safe area that’s only for your Shih Tzu during their heat cycle. Put their toys in this area and make it a place where no male dogs can approach her and there’s nothing that she can destroy. If she starts to nest, that’s a basic instinct, let her and provide her with old clothes or newspapers she can use.
  • Play with your female Shih Tzu and do activities at home with her to compensate for her decrease in outdoor activities during the heat cycle.

Tips To Prevent Your Male Shih Tzu From Chasing Females

In males, even the neutered ones, they can still smell the irresistible aroma coming from the female dog in heat. The only difference for a neutered male is he won’t release any hormones that will change his behaviours or make him aggressive.

When you are aware of the existence of a female dog in heat around your male Shih Tzu, try to do the following:

  • Walk your Shih Tzu on a leash so that they won’t continue to follow a female in heat. Even a well behaved dog can show unusual, unruly behavior.
  • Organize your trips to the park. Make sure you know if there are females in heat around the park, or your preferred walking areas and only go if they are not there.
  • Another option is to change the usual places that they play if you know any female dogs are in heat nearby.
  • Train your Shih Tzu correctly, teach them with basic commands so that you can discipline them properly and they won’t run off chasing female dogs in heat (though even with well-behaved males, there is a chance they will ignore you).

Spaying Your Shih Tzu

Once started, a Shih Tzu heat cycle will continue for the rest of a female dog’s life until you decide to spay her. Since it’s unhealthy for an elderly female dog to still go through this cycle a few times a year, it’s important to have your dog spayed once she’s been bred because heat cycles are not good for her health once she’s older. 

If you don’t have the intention of breeding your Shih Tzu, it will be best for her to be spayed after her first heat cycle. Some might recommend doing this before she has her first cycle but it’s important to let the hormonal development run its natural course. Spaying can reduce the chances of your dog getting cancer of the ovary and the mammary glands.


Hygiene During the Heat Cycle

Although the Shih Tzu heat cycle might not be noticeable just by looking at the dog, over time you will notice accumulated discharge on the bedding and other areas where your dog usually rests.

Because of these reasons, you’ll want to do the following:

  1. Your dog is likely to clean herself more often, you can help with their hygiene and some owners prefer using special heat diapers.
  2. Wipe her genital area and the surrounding area daily.
  3. Give her baths more frequently. As long as you are using a quality shampoo, you can give her a couple of extra baths.

Pain During the Heat Cycle

Even though no one can say for sure that Shih Tzus experience pain during their heat cycle, it’s been observed by professionals that female dogs are aware of their cycle and may feel some discomfort due to cramping just like humans do.

Whether it’s because of nesting behavior, cramps, or both, it’s not common for a female dog to want to be isolated. If your dog is showing signs of discomfort, it will help to place something warm near her belly. 

Keeping Your Shih Tzu Safe During the Heat Cycle

keeping safe your shih tzu in heat cycle

You’ll never know when an unneutered stray dog may show up around your female Shih Tzu. Even if your Shih Tzu stays indoors most of the time, if she has been outside to pee, her scent will be left outside which will attract a lot of male dogs which are known to run across rivers, jump fences, and go through any terrain to find a female in heat.

For this reason, we advise you to keep your dog away from public areas like dog parks. If you take her outside to pee, make sure to scope the area beforehand. If she’s approached by other dogs, pick her up and move her to a safe area.


Heat cycles are normal in Shih Tzus as it’s something that’s natural to them. During the heat cycle, make sure to take care of your Shih Tzu properly to make sure that they go through the cycle smoothly. 

If you have a female Shih Tzu, keep her away from male dogs so as to not have them following your Shih Tzu around. If you have a male Shih Tzu, scout that areas that he’s usually around in to make sure that there are no female dogs in heat that might affect his behaviors.