Your female dog will be in heat for about three to four weeks, once or twice a year. The dog heat cycle begins when your pup starts releasing the hormones that enable her to become ready for mating. Mating hormones will make your female dog more appealing to any local fertile male dogs, but you protect her from their advances by making sure your home and back yard are secure. Avoid taking your female dog to places where there may be entire male dogs during their heat cycle.
Physical signs of the dog heat cycle commencing include a swollen vulva, discharge, bleeding and an increased urge to clean themselves. When you pet them your dogs tail will curve around over their back in an action called flagging. Your female dog might also surprise you by exhibiting more masculine traits during this time like humping, raising a leg to pee and may even become aggressive. However, most dogs in heat remain in great health and good spirits throughout their season. Female dogs are however vulnerable to health issues during the few weeks following each season, so you need to keep a close eye on your female at this time. And if your dog is coming into heat any more frequently than every four months it is worth speaking to your veterinarian, as this can be indicative of health problems.
How Long Does A Dog Stay In Heat?
Being in heat is also known as coming into season, and most female dogs will come into season twice a year throughout their lives unless they are spayed. These are averages however. Many factors which can influence the age at which your female dog starts her first heat, how long her heats last, and how often she comes into season
If your female puppy is nearing maturity and hasn’t been spayed, she is about to undergo some changes. We are going to dive into the world of female dogs to discover what your dog’s heat cycle involves. We’ll also explore how female dogs behave when they are in heat. You’ll find out what to expect from your dog’s first season, and how you can best care for your dog during this time.
Do dogs have periods?
Female dogs don’t have a monthly periods or bleed in the same way that human females do. Bleeding is a natural aspect of their reproductive cycle but only takes place on average twice each year. The time during which this bleed occurs is called the heat or season.
Unlike most human females during a period, your female dog is highly fertile during their heat. This is the only time of the year during which dogs will mate and can conceive. So your Lab must be managed carefully during her heat in order to avoid pregnancy.
Your dog’s first heat
An unspayed Lab will likely have her first season any time from six months of age onwards. The average age is between nine and twelve months. Dog heat can start as late as eighteen to twenty four months old in larger breeds.
How often do dogs go into heat?
Your female Lab’s season will normally form a fairly regular pattern. Although the pattern may vary widely from dog to dog. The space in between seasons will usually be somewhere between every six months and annually. For example, one of our female dogs is every six months like clockwork. Another has only one season per year.
An eight to ten month cycle is longer than average but still considered to be normal. Occasionally a female dog will come into season every three or four months. Although the average is six months, variations in heat cycles is normal. However, it is a good idea to chat to your vet if your dog’s heat cycles are very different. This is especially true if they suddenly change to a new pattern. This is just a precaution in case there is an underlying health issue that needs looking at. Before we look at what to expect when your dog is in heat, you might find it helpful to understand how the dog heat cycle works.
The dog heat cycle – oestrus and proestrus
As she reaches maturity, your female dog produces hormones which sets a rhythm in motion. This hormonal rhythm controls the fertility of your dog and carries on throughout her life. This hormonal cycle is composed of four stages:
The Anoestrus Stage of the Dog Heat Cycle.
This is the period of time when your female is not in season. It literally means ‘no heat’.
During this period your Labrador is not sexually attractive to male dogs and she cannot get pregnant.
The Proestrus Stage of the Dog Heat Cycle.
This is the first stage of her heat cycle. During this time her uterus (or womb) is being prepared for pregnancy. As her vulva swells and she starts to bleed, you become aware that she is in heat. During proestrus your female dog will be attractive to male dogs but not yet likely to willingly permit a male dog to mate with her.
The Oestrus Stage of the Dog Heat Cycle.
This is the second stage of the heat cycle. This is when your dog becomes fertile. At this point her bloody discharge may become paler and more watery. She will probably be willing to stand and allow a male dog to mate with her. Indeed she may be very flirtatious and encouraging to male dogs. Some females will actively seek to escape from their homes to find the boy dog of their dreams!
The Dioestrus Stage of the Dog Heat Cycle.
In a wild dog, this will almost always result in pregnancy and whelping. In domestic dogs, we usually prevent pregnancy. Indeed most Labradors never have puppies because Lab owners rarely breed their dogs.
During dioestrus the levels of progesterone that would normally support a pregnancy can cause problems. False pregnancy and infections of the uterus (pyometra) are very common during this period. At the end of dioestrus your dog’s hormones fall as she returns to anoestrus. These four stages will repeat each season.
Dog Heat Signs
There are usually some clear signs when your dog is in season, but it is not always obvious so if you think she might be approaching that time you need to keep an eye on her.
Physical appearance and swelling
The first thing you are likely to notice is that your female dog’s vulva (external genitalia) becomes very swollen and puffy. It may be literally three or four times its normal size.
Together with a bloody discharge, these symptoms tell you that your female dog has come into season. As your dog moves into her fertile phase, the bleeding may stop or become more watery. Although you might expect the main sign to be profuse bleeding, it isn’t always obvious. In fact, sometimes all you will see are very small markings on the floor or in the dog’s bed.
Increased cleaning and licking
Most Labs are very good at keeping themselves clean. This can provide another good sign that she is in season. If she is swollen as well as licking her genitals considerably more than usual, her heat has probably started.
Dog Heat Test
If you are not sure whether or not your Labrador is bleeding, gently wipe a piece of clean cotton wool or a white tissue over her vulva. You’ll probably see some pink staining if she is on heat, even if she is keeping herself pretty clean.
Dog Heat Behavior
You might notice a slight change in her temperament a few days before you see any physical signs that your dog is coming into season.
These could include increased sleepiness, or her showing more of an inclination to ‘be together’. Some female dogs will be very clingy to their owners around this time. Others will be more excitable than normal in response to the changes in estrogen. They may also show some odd behavior, such as cocking a leg to pee in the manner of a male dog.
Humping and flagging
Many female dogs will also hump other dogs, male or female, when they are on heat. Some female dogs, especially puppies, will hump other dogs in play. So, if there are no other symptoms, humping does not mean your dog is in season.
Flagging is when she turns her tail to one side when you run your hand down her back and over her rump. This behavior usually takes place during oestrus when she is ready to mate.
How long does your dog stay in heat?
If your female Lab is over four months old, here are some signs you can check for. One indicator is to check if she has a swollen vulva. Another is to check for pink staining when you wipe her vulva. This should be done with a clean white tissue or cotton wool. These are both signs that your dog is almost certainly on heat.
If you experience any unusual or worrying behavior such as throwing up or loss of appetite, please consult your vet. It’s worth noting that being in season doesn’t increase your female lab’s need for calories.
If you are worried or not sure, do chat to your vet over the phone. Don’t take her into his surgery without talking to the vet first, in case there are male dogs in the waiting room. Your priority now is to make sure your dog in heat does not become pregnant. We’ll look at that in a moment. But first let’s find out how long dogs remain in heat.
How long will my dog stay in heat
The length of a season may vary. On average, your female dog’s heat will last approximately three to four weeks. The time that she will ovulate is about ten days to a fortnight in. At this point the color of her discharge may change from pink to colorless and her flagging will increase.
How long your female dog spends in each stage of her heat (proestrus and oestrus) varies widely from dog to dog. On average oestrus begins 7-10 days after the start of your dog’s season, but you simply cannot assume that she will be average.
Without getting your vet to carry out tests, it is very difficult to tell exactly when your dog is fertile. For that reason, you must assume she could get pregnant at any point after the first symptoms of heat appear. For the next three to four weeks, you should assume she could get pregnant.
Keeping track of your dog’s heat cycles
Make sure to record the date in your diary when your dog comes on heat. In addition, make a note that she may come on heat again in about six month’s time. That way you’ll be prepared and ready to look out for the signs in future. Many dogs do have a regular pattern to their cycles, which you will be able to spot with careful record keeping.
Can my dog have puppies in her first season
There is a risk of pregnancy during any time that your female dog comes into season. This includes the very first time.
If she is on heat, she will be susceptible to male advances, and may conceive if mated with.
But this does not mean that this is a good idea.
Most Labs are still puppies, very young and physically immature at the time they have their first season. It is not good for them to be mated at this stage.
There is also a greater risk of problems during whelping if they do conceive.
During her first season, your Labrador Retriever is likely too immature to cope with a litter of puppies. Nor is she likely to show good maternal instincts.
You will also find that some of the health tests you will need to have carried out to ensure the future safety of your dog’s puppies cannot be screened by this point.
If you are thinking of breeding from your Lab at some point, do check out this article for more help and guidance on making the right decisions.
Prevention Pregnancy During Dog Heat
A serious word of caution is required if you are intending to keep an entire male dog with an unspayed dog.
During her season they will need to be kept completely apart, ideally in a different house! Here’s why.
Separating your own dogs while your dog is on heat
You can try and separate your dogs at home. However, this can be a bit risky, depending upon your dog’s personality. It is also very easy to underestimate just how high a dog can jump if he really wants something special!
It is amazing just how quickly dogs can mate when you don’t want them to. All it takes is for one person to leave the door open for a couple of minutes.
Male dogs may become distressed
Your male dog will be able to tell that his female friend is on heat. He will be even more keen than normal to be in her company.
He may scratch and howl at the doors between them relentlessly, or pace up and down whining. This is both stressful for you to watch and listen to, and upsetting to both of your dogs.
Will brother and sister dogs mate?
YES! Please note, that dogs have no concept of ‘incest’. The fact that your dogs are brother and sister will not prevent them mating. If they do mate, any puppies will be greatly at risk from inherited diseases due to their similar genetic makeup.
But what about the morning after pill for dogs?
You might think that there will be an injection or pill that will put things right if you make a mistake and your dogs get together. Unfortunately, these hormonal injections have been found to be very risky for dogs and they are no longer used.
So if your dog gets mated, there is no easy way out the situation.
Alternatives to walks for dogs in season
A lot of people wrongly believe that it is harmful for their dog in heat not to be walked. This simply is not true provided the lack of exercise is temporary.
As long as she is well stimulated both mentally and physically, your female dog will be fine going without a romp in the woods for a few weeks.
Plenty of dogs have to go on crate rest for weeks after surgery and survive without any ill effects.
Clicker training is great for this, as it is a fun, rewarding way of improving training and occupying your dog’s brain too. If your dog doesn’t retrieve, you could even teach her to fetch while she is confined to home and yard.
Dogs continue to cycle through the four hormonal phases throughout their entire life. So, if you don’t have your female dog spayed, she will continue to come into season every six months or so.
The Labrador Site Founder
Pippa Mattinson is the best selling author of The Happy Puppy Handbook, the Labrador Handbook, Choosing The Perfect Puppy, and Total Recall.
She is also the founder of the Gundog Trust and the Dogsnet Online Training Program
Pippa's online training courses were launched in 2019 and you can find the latest course dates on the Dogsnet website