It’s important for you to understand that all animals (including humans) go through a menstrual cycle that is similar to the one experienced by women. In addition, the menstrual cycle for dogs differs from that of humans. When a female dog reaches puberty, she experiences her first menstrual cycle. Puppies normally show signs of sexual maturation between six and eight months of age, though this varies from dog to dog. Female dogs tend to go through regular menstrual cycles by the time they reach adulthood.
Female dogs normally go into heat twice a year, during which time they will be receptive to mating. We will now take a closer look at the various phases of the dog’s menstrual cycle. How does it form and what exactly happens during each one of these stages?


Stages of the dog’s menstrual cycle
During each cycle, dogs go through four different stages. When the female dog reaches six months old, she starts her first menstrual period. And that means that she begins to get periods herself.
1. Proestrus Stage
Proestrus is the first phase of the menstrual cycle for dogs. During the time before ovulation (when menstruation begins) there will be an increase in blood flow into the vagina. Also, during this period there will be an increased production of cervical fluids. The first signs include swollen genitals. It’s one way to identify when a dog has begun its period of heat. In dogs, these symptoms occur during each menstrual period, approximately once every six months or four months, depending on the breed. You might notice that dogs lick their genitalia more frequently during the proestrus phase. Drinking more water and urinating more. As a result of hormonal changes within the body, it’s not the right time for males to come into heat.


2. Estrus Stage
When dogs go into the estrus stage, they become sexually active and their bodies produce hormones that cause them to be ready to mate. It normally takes from 9–14 days to complete. A female dog mounts a male dog when she wants him to mate with her. She approaches him from behind and then turns her head so he has an easy time mounting her. She may attempt to go out into the yard more frequently than usual. She has followed her instincts by breeding. As far as we know at this point, the female dog has already ovulated and her blood flow through the vagina has decreased. As it turned out, the red mucus was converted into a pale-colored one. A female dog that has been bred during this period will likely become pregnant if she isn’t separated from the male dog until after the mating season ends.
3. Diestrus Stage
At this point, the dog has stopped producing eggs for breeding purposes. During these two months, her vulva will return to its original size. Females dogs won’t allow male dogs to mate anymore. As the female hormone estrogen decreases, testosterone increases.
If the dog has been bred, she will start becoming pregnant during this time. During pregnancy, you need to be especially careful when caring for your pet. Foods can be modified. You need to focus on foods that provide more protein for strengthening the bodies of both dogs and puppies. Another uncommon condition during pregnancy is pseudocyesis. Pregnancy can be detected by observing her behavior caused by hormonal changes but there won’t be any puppies in the uterus when they pass through. It will go back to its original state by itself.


4. Anestrus Stage
The final stage is the Anestrus stage of the dog heat cycle, also known as the resting period. After the mating season has ended. She will be resting her uterus. Genital Swelling has gone down to normal size and there’s no longer any mucus coming out. Depending on the species, this rest period may last for three to four months. Large breed dogs have a longer rest period than small breeds. At the end of which the whole heating cycle begins once more.


What are the signs of heat
At the start of their menstrual cycle, dogs show signs of physical changes due to hormone levels changing. And they express behaviors differently than usual. Common Signs include these:
- Pay more attention to male dogs
A female dog will always approach a male dog. Walkthrough and cuddle with her, but don’t let him mount her. If he starts mounting her, she’ll be more defiant and leave.
- Drink lots of water
During periods when there is dilation of blood vessels and increased amounts of mucous in the vagina, dogs tend to be fussy and eat more often than usual. In contrast, your male dog may ignore any opportunities for food or water because he has an instinctive focus on mating. You can get some helpful advice about persuading your dog to drink water by avoiding dehydration.


- Licking genital
During menstruation, the female dog goes through physical changes including enlarged genital. It may be uncomfortable and unfamiliar for some dogs, especially dogs who are first menstruating. A dog will lick its genitalia more frequently than normal.
- Become more affectionate or cheerless
Changes in the body may cause the dog to feel unfamiliar, uncomfortable, and sometimes even lethargic. And would like to be able to come closer to the owners’ legs even more. Being especially irritable during menstruation is similar to being particularly querulent.
In addition, she may become excessively friendly toward other dogs or lose their desire for social interaction with humans. She may experience a swollen vulva, bloodstained vaginal discharges, and increased frequency of urination.


How to care for a dog in heat
During her menstrual cycle(female in heat), the female dog needs extra attention because she becomes sexually receptive during that period. Her hormones will start fluctuating. If your dog needs extra care during her period, here’s what you can do for her.
- It’s important for us to show our appreciation by giving her extra affection and attention. It may be something simple like petting her more, grooming her, or even just giving her an extra hug.
- It may be helpful for her if she keeps herself occupied by doing something else besides focusing on her pain.
- Waking more often may help her feel refreshed and less anxious.
- Dog owners may use pet pampers to keep their dogs clean by preventing them from having any kind of impurity inside their bodies. Besides keeping things clean, and giving her what she needs, whether it’s attention or space.
- Provide a safe place where she can rest during naps. And if she feels anxious, then give her some toys or another blanket to help calm her down.
- To avoid dogs experiencing fatigue due to dehydration, you need to increase their water intake by increasing its frequency or quantity.


Conclusion
Once the puppy reaches six months of age, he/she will start entering into heat cycles. Female dogs go into heat during their proestrus period, which usually lasts for seven to fourteen days, depending on the dog’s age and breed. The mating season begins when menstruation starts.
When dogs go through puberty, their bodies change dramatically both physically and emotionally. If you don’t want to get a puppy, separate the females from the males for at least 2–3 weeks. If you wish for a dog, then you may choose when it will become pregnant naturally. During dogs are menstruating, until they’re feeling sleepy, losing their appetites, or want to eat something picky choose the best foods for them.