The topics of sexuality and fertility in female dogs are temporally well-defined. Only once or twice a year, during the phase known as the heat cycle, are female dogs receptive to the advances of males and can become pregnant if mating occurs. So, if you don’t want unplanned offspring and want to assess your dog’s behavior correctly, it’s essential to be well-informed about the heat cycle. We’ll explain what you, as a dog owner, need to know about the heat cycle, how to recognize the fertility phase, also known as “heat,” and the differences among various dog breeds.

When does a female dog experience her first heat cycle?

The occurrence of a heat cycle in practically every unspayed female dog is certain at some point. However, the exact timing of a female dog’s first heat cycle is individual and depends on her health, development, and, in particular, her size. The range varies from six months to two years. Here’s a brief overview:

If your female dog hasn’t experienced a heat cycle even after this period, it’s crucial to consult your veterinarian. There might be a hormonal or health-related issue behind the absence of the heat cycle.

How often do female dogs go into heat?

This also varies significantly from dog to dog. The frequency of a female dog’s heat cycle each year depends on individual factors and her breed. Additionally, the fertility phase occurs much more irregularly in the first two years than in later life stages. On average, most female dogs become receptive every 6-7 months. The influence of the breed on the frequency of the “heat” cycle can be found in the following table.

Breed Size Frequency:

Duration and Phases of the Heat Cycle in Female Dogs

An average heat cycle lasts for about 21 days, approximately three weeks, although this period can be longer or shorter depending on the individual dog. It is divided into four different phases of varying durations, the occurrence of which also depends on whether fertilization occurs or not.

Pre-estrus:

Estrus / Heat:

Post-estrus (Metestrus and Diestrus):

Anestrus (Resting Phase):

Detecting Heat in Your Female Dog – Watch for These Signs

There are several physical signs and behaviors that can indicate when your female dog is entering the heat cycle. These signs include:

However, it’s important to note that the phenomenon of “silent heat” exists, where your female dog shows no symptoms of being in heat. In such cases, the behavior of eager male dogs may be the only clue.

Does a female dog undergo permanent changes with the first heat cycle?

The answer is a definite yes. While the acute symptoms of heat eventually subside, a permanent change in behavior is not uncommon. This is not unusual or alarming because the first heat cycle marks a transition to adulthood for the female dog. The hormonal balance undergoes significant changes, leaving traces on the character and behavior, much like in human beings. However, a complete reversal in personality is unlikely, and the changes that occur do not necessarily have to be negative. Be understanding if your female dog behaves somewhat differently, such as being less playful or cuddly than before. She has simply matured.

Dealing with Female Dogs in Heat

When your female dog is in heat, you cannot go about your daily routine as usual. It starts with being vigilant during walks. Always be on the lookout for intact males and try to keep them away from your female dog as much as possible. If you encounter a male during walks, it’s better to avoid them, inform their owner about your dog’s heat cycle, and ask them to keep their distance. Additionally, you can tie a yellow ribbon to your female dog’s collar, harness, or leash. This code signals to many dog owners that your female dog needs some space.

Off-leash activities in the dog park are now possible only if there are only other females or neutered males present, and you should always keep the leash ready for emergencies. If you cannot oversee an area well and are not confident about reacting quickly to newcomers, it’s better to keep your female dog leashed during this time. In general, grant her only as much freedom as necessary and choose walking routes where she encounters other dogs as infrequently as possible.

Especially indoors, a heat diaper for your female dog is indispensable during this time. These diapers, available in pet stores, are washable, can be lined with a sanitary pad, and help prevent bloodstains on blankets, beds, couches, or furniture. However, they do not protect against fertilization.

Even if you are vigilant, it is not excluded that your hormone-driven female dog might escape from you in a careless moment and go in search of a suitable partner. For such cases, it is advisable to attach a GPS tracker to your female dog’s collar or harness. This way, you always know where she is in case of an emergency, protecting her not only from unwanted mating but also from accidents or potential abductions.

Reaction of Male Dogs to Females in Heat

If you are the owner of a male dog, you should be particularly cautious when a female in heat is nearby. This also applies to neutered males because, quite often, the interest in the opposite sex persists despite castration. Even if pregnancy is ruled out, your dog might attempt to mount and mate with a female, leading to potential issues even without unplanned offspring.

If your male dog is intact, you must be even more cautious. If he mates with a female against the owner’s will, you may be legally responsible. Therefore, it’s better to be cautious and, when in doubt, keep your dog on a leash. Especially if he shows increased interest in females, responds less reliably to recall, pulls on the leash, or exhibits warning signs such as loss of appetite, restlessness, and frequent barking that your veterinarian cannot attribute to a medical cause. In any case, it’s a good idea to have dog liability insurance. This insurance covers the costs in case of an unintended mating.

How to Prevent Heat?

The safest and most reliable method is spaying. It not only prevents pregnancy but also significantly influences hormone levels and interrupts the female’s heat cycle. Additionally, spaying slightly increases life expectancy, and if done before the second heat cycle, the risk of mammary tumors decreases. However, spaying also increases susceptibility to certain types of cancer, and negative effects on bone development, thyroid, coat, and weight cannot be ruled out.

An alternative to spaying is the use of hormonal injections, which need to be administered every five months. It has the advantage of not being permanent, allowing the possibility of pregnancy again after skipping a dose. It also does not require a surgical procedure. However, interfering with the hormone balance can lead to side effects such as overweight or lethargy. Besides hormonal injections, there are other hormonal treatments, such as estrogen therapy. However, these contraceptive methods are not free of side effects and, in some cases, increase the risk of certain diseases like uterine infections.

Since all these methods – just like abstaining from treatment – have pros and cons, you should weigh them carefully and seek advice from your veterinarian.

Does a Female Dog Experience Menopause?

No, a female dog cannot go through menopause. Unlike humans, she remains fertile throughout her life. However, the heat cycles become less frequent as female dogs age. Additionally, the health condition of the female dog must be considered before planning a pregnancy, as it can become a potentially life-threatening burden for an older dog.

What Should I Do if My Female Dog Is Mated While in Heat?

For such cases, there is a kind of “morning-after pill” or rather a “shot afterward” for dogs. However, because this “anti-hormone injection” carries health risks due to the high hormone dose, this step should be carefully considered. Alternatives, such as finding interested parties for adopting the puppies, should also be considered if you don’t want or can’t care for them yourself. A post-mating spaying can also prevent unwanted offspring up to the 40th day of pregnancy. It’s best to consult with your veterinarian on this matter.

In the case of an unintended mating, you also have the right to support from the owner of the mating dog. They must cover the costs of abortion or raising the puppies and also bear responsibility for any consequential damages. If the owner is insured, their insurance must cover these costs. An unintended mating in dogs is thus legally protected.

If the pregnancy was planned or if you decide to let your female dog carry her puppies after an unintended mating, you might be interested in our tips for pregnant dogs and the birthing process in dogs.