Female beagles, who are not spayed, go through an estrus cycle during which they are fertile. It’s somewhat equivalent to a human female’s menstrual cycle and is also referred to as being “in season” or “in heat.” It typically occurs seasonally, around twice a year in the fall and the spring.

If you own a female beagle, you’ll see her going through a lot of changes throughout her cycle and it’s good to know what to expect and what to look for as signs. During the time that she is in heat, she will be very attractive to any male dogs, so – unless you are planning on breeding her – it is vital that she does not have contact with other dogs.

Knowing the signs and how the heat cycle works can help you keep your beagle more comfortable, monitor her fertility and keep an eye out for any possible concerns.

When Does the First Heat Cycle Start For Beagles?

Unlike humans, female beagles do not enter into menopause, meaning that – in effect – they are fertile for the majority of their lives, if left unspayed. Beagles can continue to go into heat well into their later years.

The onset of the first heat cycle in beagles varies from dog to dog but typically starts fairly early – often as young as four to six months of age. Occasionally, a beagle’s first heat cycle will be delayed, and can occur as late as a year to 16 months of age. There are numerous signs you can look for to indicate when she is entering her first heat cycle, as discussed below.

When your dog starts her first heat cycle, it is normal for these cycles to be somewhat irregular and not perfectly spaced out by six months. It can take up to two years for female dogs to reach a regularity with their cycles, as they still need to fully develop and grow themselves too. Two years of age is recommended as the best age to start breeding beagles for this reason.

Although beagles are fertile at a very early age, it is not advisable to breed such a young beagle. The American Kennel Club recommends waiting until your dog is at least two years of age to consider breeding. A young dog of six to twelve months may be physically able to achieve a pregnancy but is at risk of all sorts of complications, as – at that age – she is not even close to being fully physically developed herself. When a beagle of that age becomes pregnant, it is at the expense of her own continuing growth and health.

Most female beagles retire from being bred by the age of seven, although they may be able to get pregnant for many years past that. Once your beagle has retired, vets recommend getting her spayed so that she can enjoy the many health benefits that it imparts. It will also save you, the owner, from having to deal with the occasionally-problematic health or behavioral problems that can accompany your dog being in heat.

What Exactly Is a Heat Cycle?

Your female beagle’s heat cycle is just that – a cycle. She will go through three different, distinct phases during this cycle – proestrus, estrus and diestrus. While a lot of dog breeds only experience heat once per year, some smaller breeds like beagles will go into heat every 6-7 months, most often in the fall and again in the spring. In more detail, the stages of the heat cycle are:

• Proestrus

During the proestrus phase, you probably won”t notice any real changes in your beagle’s behavior or her physical state. During this time, the level of the hormone estrogen in her body begins to rise, setting the stage for estrus. It is this hormone that signals the body to release eggs, as well as affecting behaviors that make the dog attractive to potential mates.

This stage lasts from anywhere between 9 and 27 days, and typically happens right before the Estrus stage starts.

• Estrus

During this time, your beagle’s level of estrogen is at a peak and she will be very receptive to breeding. Estrus is also when your dog will ovulate, meaning that there are eggs ready for fertilization. It’s during this time that she’ll exhibit many of the behaviors that are typically associated with the heat cycles of dogs (see below for details). This period can last from a few short days to over two weeks.

• Diestrus

This is the period that follows the fertile time (estrus). At this stage, your beagle will no longer be receptive to mating and is not capable of becoming pregnant (due to the fact that they likely are already pregnant). The estrogen levels in her body will drop and, instead, progesterone levels increase.

Whether or not your dog is pregnant, you will see big changes in behavior as she returns more to her “normal self.” Pregnancy symptoms will slowly begin to emerge during this time but, for the most part, diestrus is fairly uneventful.

• Anestrus

Anestrus is characterized as the time between the diestrus stage, birth, and the next proestrus stage. This stage tends to last for about four months, but can be much longer, and tends to follow birth. During this phase, the vulva is no longer swollen, and there is no more vaginal discharge. In this stage, the body takes time to allow the uterus to heal and prepare for the next possible pregnancy, starting with the proestrus stage that follows.

What Are the Signs That A Beagle Is In Heat?

There are numerous signs that you can look for to tell you that your beagle is in heat. Other signs are visible only via testing at your vet’s office. At home, you can look for the following:

• Behavioral changes

These may be less obvious during proestrus, although some beagles do get more withdrawn or – conversely – overly affectionate. During proestrus and estrus, your dog may seem like a “whole new girl!” She will exhibit a range of behaviors that make her more attractive and available to a mate. This might include frequently lifting her tail, wanting to go outside constantly, being overly affectionate/attention-demanding and whining.

Dogs can also get confused during this time and not exactly know how they should be have. Some beagles tend to isolate and get more withdrawn, while others get much more affectionate.

They may also get more agitated around dogs, particularly male dogs, and may actually run away from them instinctively, especially if male dogs can sense that they are in heat. Alternatively, they may actually pay more attention to male dogs because of their hormonal changes, it really fluctuates on a case by case basis for each individual dog.

Regardless, if your dog is in heat and you are worried about male dogs potentially getting her pregnant, you’ll have to be pretty diligent. Because of the hormones she’ll be emitting, male dogs will be able to sense her from about a three mile radius. You’ll want to be careful on walks, and extra careful at dog parks or beaches, anywhere she could be off leash and around male dogs.

Some beagles experience a good deal of discomfort, akin to human menstrual cramps and it will show in their behavior. They might curl up or sleep more, for example. If your beagle is excessively whining like they are in pain, at around the 5 month age, it could be because of the proestrus phase. You should consult with your vet to confirm, and if you want to get her spayed, now is the time to start putting that planning in place. 

• Excessive Urination

During estrus, your beagle will urinate frequently. This is her way of marking her territory with pheromones, which alerts male dogs that she is in heat and receptive to breeding. This discharge will increase during estrus.

It’s important to strive to keep your dog extra hydrated during this phase, as the excessive urination can contribute to dehydration, especially if it happens to take place during hot summer months.

• Changes in activity levels

This can be a hard symptom to pin down, as while most female beagles will become more energetic and excited or even frenzied acting, others will withdraw and be quieter. Those who gain energy will have an accompanying increase in hunger to accommodate their increased caloric needs.

You should pay attention to how your beagle is responding to their normal walking schedule. If they appear to have more energy than usual, or get more tired out by your regular walks more frequently, this could be a sign of the estrus stage of their heat cycle.

In addition to the signs that you can look for at home, your vet can also check for additional signs that your beagle is indeed in heat. Your vet can assess things like changes in the thickness of the uterine lining, for example. Vets can also take blood samples in order to measure hormone levels. Both of these are good indicators of where a beagle is at in her cycle.

You can learn more about how to care for dogs in heat in the video below:

Complications and Risks of Beagle Heat Cycles

The biggest potential risk from beagles going into heat is a condition known as Pyometra, which is an infection of the uterus.

Pyometra is often the result of hormonal changes in the uterine lining that take place during the proestrus and estrus phases of a dog’s heat cycle. It mostly occurs when a beagle doesn’t get pregnant during the estrus phase, because progesterone levels continue to remain high, which can result in increased thickness in the uterine lining until cysts start to form. These cysts can secrete fluids that can be breeding grounds for bacteria, which can lead to seriously dangerous bacterial infections.

Unfortunately, if not caught early this condition can be fatal, which is why it’s very important to get your dog spayed if you are certain that you don’t want to breed them. It is rare, but you should consult with your vet about the pros and cons of allowing your dog to go through heat with no intentions of pregnancy.

Additionally, the biggest complication of heat cycles is an obvious one – unwanted pregnancy. If you’re not a breeder, an unwanted dog pregnancy can cause a lot of behavioral changes in your dog that you might not be equipped to handle. Also the increased vet visits to keep your dog and her puppies safe will require a lot of work, time, and money. Lastly, you’ll have to figure out how to help your beagle through the birthing process, and how to care for all those puppies!

How Does Beagle Spaying Work?

Spaying your beagle not only keeps unwanted litters of puppies from being born into a world already struggling with a pet overpopulation problem, it also offers additional health benefits.  This is why, even if you intend to breed your beagle, vets and organizations such as the American Kennel Club recommend that you have your dog spayed after she has retired from having puppies.

A spayed beagle is less likely to wander (and possibly get lost or injured) because of their more regulated behavior and activity levels. She will also be calmer, and will not experience the discomfort that so often accompanies being in heat. In addition to behavioral advantages, being spayed also offers protection from diseases, such as uterine and breast infections, which can lead to malignancies. The earlier your dog is spayed, the more protection that is conferred, especially since spaying at a young age can prevent breast development and the hormonal changes of the late part of the estrus cycle.

If you are not planning on breeding, it is advisable to have your beagle spayed before she goes into heat for the first time, or at the very latest between her first and second heat cycles. 

You can have the spaying surgery done by your own vet. However, most counties or cities also have low cost spay and neuter options that are subsidized by either government funding or a local pet welfare organization, as a means to control pet overpopulation.

Cost should not be a factor in deciding whether or not to have your pet spayed. For information on finding low cost services look up the ASPCA or your local animal shelter.

It’s natural to be concerned about taking your pet in for surgery. It’s important to understand that spaying is a relatively simple procedure that carries less of a health risk than the estrus cycle and pregnancies. Your beagle will be put under anesthesia throughout the surgery, which involves removing some of your dog’s reproductive organs – the fallopian tubes and the uterus.

After-surgery recovery is typically pretty uneventful but you will want to keep an eye out for any potential complications. Your vet can prescribe medication to help your dog deal with any post-op pain. Your job as an owner during this time is simply to keep your beagle calm, monitor the incision site for any signs of infection, follow your vet’s recommendations and allow your beagle to get some rest.

Your dog may have to wear a cone depending on the incision site, and their own size, in order to prevent them from opening the wound, which can lead to infection. So as an owner you’ll want to remain diligent and make sure that you’re following your vets instructions – it will save you headaches, extra visits, and a lot of money in the long run.

You will be scheduled for a post-operative checkup so that your vet can make sure that healing is going well. Spend this time giving your beagle extra well-deserved cuddles. She will be back up and running around like crazy before you know it!

Final Thoughts

Understanding your beagle’s heat cycle can help you to be a more informed owner and to make the best decisions for the health and well-being of your dog. If you are planning to breed your beagle, veterinarians still advise that you consider spaying after your dog has retired from having puppies. The health and behavioral advantages will be well worth the effort.