Do Dogs Personalities Change After Heat?

A female dog’s heat cycle, also known as estrus, is a normal biological process. During this time, her hormones fluctuate wildly in order to prepare her body for pregnancy and motherhood. While the most noticeable changes occur physically, many owners report differences in their dog’s personality and behavior during and after their heat cycle.

These changes can include increased aggression, neediness, restlessness, anxiety, appetite changes, and general moodiness. The exact causes of these temperament shifts are not fully understood, but are likely due to the hormonal rollercoaster. Most dogs do return to their normal selves, but some may experience lingering effects.

In this article, we will explore the common personality and behavior changes that occur before, during, and after a dog’s heat cycle. We will also discuss potential reasons for these changes, ways to manage them, when you should seek vet assistance, and how to prevent issues down the line. The goal is to provide dog owners with a comprehensive guide to understanding their dog’s evolving temperament around their heat.

What Happens During A Dog’s Heat Cycle

A dog’s heat cycle consists of four distinct stages that occur roughly every six months once a dog reaches sexual maturity, which is usually between 6-24 months of age. The four stages are:

1. Proestrus – This initial stage lasts approximately 7-10 days. The dog’s vulva will swell and she will have a bloody vaginal discharge for around 9 days on average. Her estrogen levels are rising during this stage which leads male dogs to be attracted to her but she will reject mating attempts.1

2. Estrus – The estrus period is commonly referred to as a dog’s “heat” or being “in season.” This is when estrogen levels peak and eggs are released from the ovaries. It lasts approximately 5-10 days. The discharge lightens in color and the dog is receptive to mating. 2

3. Diestrus – After estrus, diestrus starts which lasts roughly 50-90 days. The discharge becomes watery and then dries up as progesterone levels rise. The dog’s body is preparing for potential pregnancy so she is no longer receptive to mating. 3

4. Anestrus – This is a resting period of 2-3 months where the dog’s reproductive system is inactive before the cycle starts over again. Discharge has ended completely.

Common Personality Changes

There are several common personality changes that may occur when a female dog is in heat. These are mainly related to the dog’s hormones fluctuating during the estrous cycle. Some of the most notable changes include:

Increased affection and clinginess – Many dogs become more affectionate and clingy during their heat. According to Four Paws, this is due to the rise in estrogen that occurs at the start of heat. The dog may seek more affection and attachment as a result. This increased need for attention usually subsides once the heat cycle ends.

Changes in activity levels – A dog’s activity levels may rise and fall over the course of her heat. As Preventive Vet notes, some dogs become more active at the start when estrogen rises. Later, as progesterone increases, she may become less active. Activity levels should return to normal after the heat passes.

Changes in anxiety levels – Fluctuating hormones can also lead to changes in a dog’s anxiety levels. According to PetHelpful, she may act more anxious or irritable at times, especially as testosterone rises near ovulation. Providing a comfortable space and maintaining normal routines can help manage this.

Causes of Personality Changes

A dog’s personality may change during heat due to several factors:

Hormonal fluctuations – The rise in estrogen levels before and during estrus can cause moodiness, anxiety, restlessness, and changes in appetite. These hormone changes affect neurotransmitters in the brain that influence behavior 1.

Seeking male attention – Some female dogs become more affectionate and attention-seeking during heat as their drive to mate increases. They may solicit petting, rub against furniture, or try to escape the home to find male dogs 2.

Physical discomfort – Swollen vulva, abdominal cramping, and bloody discharge can cause irritability. The dog may snap or growl if touched near her rear 3.

Managing Personality Changes

There are several things you can do to help manage your dog’s personality changes during her heat cycle:

Provide extra affection and attention. Your dog may feel anxious or need reassurance during this time, so giving her some extra love can help her feel more comfortable. Set aside some special one-on-one time for petting, brushing, massaging, or just sitting together.

Manage anxiety. Some dogs become more anxious or clingy during their heat. Using pheromone diffusers, calming supplements, or anti-anxiety medication (talk to your vet) can help ease their stress. You can also use a Thundershirt or play calming music.

Adjust exercise. Your dog may have different exercise needs during her heat. Go for shorter, more frequent walks to avoid restlessness. Provide interactive toys for mental stimulation. Avoid dog parks or daycare to prevent male attention.

Overall, remain patient and cater to your dog’s needs during this transitional time. With a little extra care and understanding from you, she’ll likely return to her old self once her heat cycle finishes.

Returning to Normal

Most of the behavioral and physical changes female dogs experience during heat are temporary and will go back to normal after the heat cycle ends. According to experts, a dog’s personality and temperament typically return to their pre-heat state once the progesterone levels drop after ovulation occurs. This is because the hormonal fluctuations that caused the changes dissipate as the heat ends.

For example, after being in heat, the vulva swelling reduces and returns to its normal appearance, as noted by PetMD. Additionally, after weaning puppies, the enlarged nipples shrink back closer to their pre-heat size. While some physical changes may not completely revert, like mammary gland development, the drastic alterations seen during heat are no longer present.

Likewise, the behavioral shifts correlated with the heat cycle tend to resolve post-heat, according to vets. Increased activity levels, anxiety, restlessness, and nervousness usually go back to normal. Most experts find that female dogs exhibit their usual demeanor and energy levels after the heat cycle runs its course.

So in summary, while heat can temporarily alter a dog’s disposition, these changes are short-term. With the fluctuating hormones gone, most dogs revert to their typical personalities once the estrus period concludes.

When to Seek Help

In most cases, personality and behavioral changes that occur during a female dog’s heat cycle will resolve on their own once her hormone levels return to normal. However, if aggressive, anxious, or irrational behavior persists well after the heat has ended, it’s a good idea to consult your veterinarian.

Some dogs may continue exhibiting signs of aggression, fearfulness, or other temperament issues for weeks or months after going through estrus. If your pet’s personality remains noticeably altered and disruptive to her normal routine even after giving her time to settle back in, seek veterinary help to rule out potential medical factors.

There are some medical conditions like thyroid disease that can cause lasting behavior changes in dogs. Your vet can run tests to check your dog’s hormone levels and overall health to determine if an underlying issue requires treatment. They can also refer you to a veterinary behaviorist if your dog needs more focused behavioral therapy and training.

Getting professional help quickly is key if your female dog’s heat cycle seems to have triggered an ongoing personality disorder. The sooner any medical factors are addressed, the better her chances of making a full recovery back to her usual happy self.

Preventing Future Issues

One of the most effective ways to prevent issues related to a dog’s heat cycle is to get them spayed. Spaying refers to the surgical removal of the ovaries and uterus, which eliminates the possibility of going into heat. According to one source, spaying can reduce the risk of mammary tumors, uterine infections, and some undesirable behaviors associated with the heat cycle (

Proper socialization and training from an early age can also help prevent personality changes during heat cycles. Well-socialized dogs are less likely to develop aggressive or fearful tendencies when going through hormonal changes. Obedience training establishes boundaries and improves a dog’s ability to cope with stress. One source suggests continuing normal training routines through the heat to provide stability (

Individual Factors

Personality changes vary between dogs based on breed, age, medical issues. Some breeds like German Shepherds tend to become more clingy and vocal while in heat. Smaller breeds may be crankier during their heat cycles. Very young dogs going through their first heat around 6-9 months old might act more erratic. Older dogs with medical conditions like Cushing’s disease or diabetes may experience more anxiety and need more supervision.

According to one source, “The intensity of the heat cycle differs greatly between breeds. While some dogs like German Shepherds retain most of their normal behavior and are minimally affected by the heat, others like Basenjis may become moody and disobedient.”

Monitoring your dog closely during her first few heat cycles will help you learn her specific personality changes. Keeping detailed records about your dog’s behavior can help identify patterns and predict what to expect during future cycles. Pay attention to factors like breed, age, and health that impact how intensely your dog experiences heat.


A dog’s personality can be affected during their heat cycle, but these changes are usually temporary. The most common changes seen are increased anxiety, neediness, restlessness and aggression due to hormone fluctuations and discomfort. However, spaying your dog eliminates future heat cycles and often resolves any problematic behavior changes. While the heat cycle can be challenging for both you and your dog, remaining calm, providing comfort, and modifying your routine can help manage personality shifts until your dog returns to normal after her cycle ends. If worrisome behavior persists, consult with your veterinarian to rule out any medical issues. With preparation and patience, this natural process can pass smoothly.

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