Knowing When Your Puppy is in Heat 

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Knowing When Your Puppy is in Heat Knowing when your puppy is in heat is important, but it can be confusing when your puppy starts showing signs of being in heat. “Heat” refers to the time in which your female dog reaches sexual maturity. This “heat” cycle has different stages, and the first time experiencing it as a pet owner can be startling. As a responsible pet parent, you want to make sure that you’re taking all the necessary steps to ensure your puppy’s safety and health. Read on for an overview of what you need to know about the typical female dog’s heat cycle.

Signs of Heat 

Around 9-10 months of age, you’ll likely see the first obvious sign that your puppy is in their first season; a bloody discharge accompanied by swelling of the vulva, caused by hormonal changes. The heat cycle for a chihuahua, for example, can occur between 5-10 months of age and usually lasts about 3 weeks. The difference is noticeable from the normal size, and this will likely be your first sign that your dog has entered the proestrus stage in the estrus cycle. This discharge will range from light pink to a bright red color, and it should be monitored closely.

As a warning, giant breeds will definitely produce more of this bloody vaginal discharge, as opposed to smaller breeds. The best way to control the mess during this time is to put your dog in dog diapers.

She may also urinate more often than usual, as this is a natural way for her body to attract potential mates. Additionally, she may exhibit behavioral changes such as increased aggression or more vocalization than normal. Once she moves into the estrus stage, male dogs will also likely come up to her and express interest, so it’s best to keep her away from the dog park or other public spaces during her reproductive cycle. At the very least, the most important thing is to keep an intact male dog away from an unspayed female dog during this time and definitely not unattended– this will most definitely lead to unwanted pregnancy.

Keep an eye out for these signs so you can help keep your pup healthy and safe during this time. Here is some more information on these changes.

Behavioral Changes 

One of the first signs that your pup may be in heat is an increase in behavior changes. With fluctuating estrogen levels, you’ll likely see personality changes as well. During this time, they may become more clingy and anxious than normal. During the diestrus stage, their estrogen levels drop dramatically, and they’ll be more low energy. They may look for extra attention or even try to escape from the environment because they feel uncomfortable or overwhelmed. You may also notice increased aggression towards other animals during this time as well. Sympathize with your dog’s behavior during this time; she is absolutely miserable!

Physical Symptoms 

Another key sign that your pup is going through its heat cycle is physical changes such as the aforementioned swollen vulva, vaginal discharge, vaginal bleeding, and heavy panting during the dog heat cycle. Don’t worry, pet parents; these are all perfectly normal in an unspayed dog and should subside within a few weeks as long as your pup gets plenty of rest and exercise during this time. If you notice these symptoms persisting longer than usual or becoming more extreme, contact a vet immediately for further advice. 

Hormonal Changes 

Finally, hormonal changes can occur when puppies enter their heat cycles. This typically means increased levels of estrogen which can result in mood swings, irritability, and even depression-like behaviors at times. It’s important to keep an eye on these changes so you can intervene if necessary with extra cuddles or other comforting activities like walks or playing fetch together outside. 


It’s important to spay your puppy if she has gone through at least one heat cycle. Spaying helps prevent uterine infections, mammary tumors, and other reproductive health issues that can arise later in life if she isn’t spayed while she’s still young. Speak with your vet about the best time to spay your pup so you don’t have to worry about her going into heat again down the line. 

Caring For Your Puppy During Heat 

Finally, there are some things you can do at home to help care for your pup while she is in heat. Make sure that she gets plenty of exercises every day, as this will help keep her active and healthy during this period of hormonal fluctuations. If possible, try walking her during cooler parts of the day when it isn’t too hot outside—this will help keep her energy levels up without putting too much strain on her body due to the higher temperatures outside. Additionally, provide access to plenty of water so she stays hydrated throughout the day! 

It’s a Cycle of Life

No matter what breed or age your puppy is, it’s important that you know how to recognize when she’s in heat so that you can take steps to ensure her health and safety during this period of hormonal fluctuation. By keeping an eye out for common signs such as bloody discharge from the vulva or increased urination frequency, you’ll be able to provide the best care possible for your pup while she’s in heat! Additionally, speak with your vet about when would be the best time to spay her so you don’t have any further worries down the road! Caring for a puppy means being prepared for whatever comes their way—especially when they’re experiencing their first heat cycle!