Adrienne is a certified dog trainer and former veterinarian assistant who partners with some of the best veterinarians worldwide.
Why Didn't My Dog Go Into Heat?
Sometimes, the signs of a dog in heat are so slight that they go unnoticed. In a silent heat, all external physical signs (like vaginal bleeding, discharge, or swollen vulva) are so minimal that you don't see them. Not only that, but her behavior might not change—she may show absolutely no interest in male dogs, either.
Understanding Silent Heat in Dogs
So, you have been waiting anxiously for your dog to go into heat. It could be you were planning to breed her this time or you simply wanted to get her spayed right after the heat. It could also be that you just wanted to be prepared, so you could take all the necessary precautions that should always be taken by owners who choose to keep their female dogs intact.
Of course, you are familiar with your dog's heat cycle. You know how often in general it happens and you know how to recognize the signs of proestrus. So, six months go by, and nothing happens. As the seventh month flies by, you start scratching your head. What happened? Did you miss it? Is your dog's heat cycle going bonkers? Did she skip her heat, or is it late? Below, we will talk about silent heats in female dogs.
What Would Cause a Silent Heat?
Veterinarians who specialize in reproductive health often meet owners who are just as puzzled as you. More often than not, the dog most likely went into heat, but the owner just didn't notice.
You may say, but what about all the male dogs? Shouldn't they have been showing at least some interest? What about the trails of adoring males waiting outside the front door? Following are some causes of what dog owners refer to as "silent heats."
The Signs Are There (Bleeding, Swelling, Discharge, or Behavior Changes), But You Don't See Them
Yes, your dog may have simply given off little signs of going into heat you may not have caught. Don't take it personally; it happens. As mentioned, countless vets are contacted for the same problem. If you were not planning to breed, count your blessings; many owners would prefer a silent heat, so they did not have to deal with all the cleaning and cranky behaviors associated with it.
But, how could you have missed it? Some dogs are fastidiously clean and will readily lick off any signs of evidence, so the bloody discharge may have never made it to the floor. Other dogs simply don't bleed much at times; these "dry heats" are not abnormal. If you are planning to breed your dog, don't rely on the presence of blood alone!
Sometimes, Dogs Don't Display Assertive Mating Behavior
Okay, so you may have missed your dog's heat cycle, but what about the other male dogs? Aren't other dogs supposed to smell a female in heat from a distance and go bonkers over it? How could your neighbor's male dog care less? Some female dogs who are aggressive or assertive may discourage male dogs from showing any interest. If your dog doesn't seem to match this type, read on for more causes of silent heats.
Silent Heat vs. Missing Heat: Medical Conditions
At times, what looks like a silent heat is actually a missing heat. If about 10 months have passed and your dog didn't go into heat, it could be you have missed the signs, but it could also very well be that your dog really didn't go into heat. Keep in mind that this can happen and at times this can be due to some medical problems. Possible conditions capable of causing a lack of heat include hypothyroidism, hyperadrenocorticism, hypoadrenocorticism, diabetes mellitus, and cancer explains veterinarian Mike Richards.
Dog Breed: Basenji, Mastiff, Etc.
So you are used to seeing a female dog cycle every 6 to 7 months? Well, forget this guideline if you are first-time Basenji or Tibetan Mastiff dog owner. These breeds tend to cycle once a year, so you know there's nothing really wrong with these fellows if they are not showing any estrus signs twice a year.
When to See a Vet
Now what? So if your dog didn't go into heat, and she's not a Basenji and doesn't seem to be planning to go into heat soon, then your next step is to have your dog seen by a vet. Have the vet rule out any medical problems. Your vet may then decide to check on your dog's progesterone levels to have some idea of what may be going on. If your dog did undergo a silent heat, her progesterone levels would still be high enough to prove that. Weekly cytology tests may provide an insight on the chances for an estrus cycle nearing or signs that nope, there's not going to be any future cycle in the near future.
Interestingly, if your dog is late in her heat and you're concerned, housing her with another intact female who is approaching proestrus may help. There are many cases, where a cycling dog may induce heat in another female dog living alongside.
This article is accurate and true to the best of the author’s knowledge. It is not meant to substitute for diagnosis, prognosis, treatment, prescription, or formal and individualized advice from a veterinary medical professional. Animals exhibiting signs and symptoms of distress should be seen by a veterinarian immediately.
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Questions & Answers
Question: I have an almost 11 month old German Shepherd. We are planning on breeding her for future service dogs; however, she hasn't gone into heat yet. Is this normal? If not, could the 2 UTIs she’s had have disrupted her heat?
Answer: One possibility is that the burning sensation of the UTI is causing her to lick. Therefore, if she is in heat, she’d lick away any discharge, causing you to miss the signs of heat. Although not very common, some dogs may go into heat as late as 12-14 months old. You might consider having a progesterone level done, as well as consulting with a theriogenologist.
Question: The last time I saw my Pomeranian going into heat was when she was 1 and a half, now she's four and I've no idea about her heat. I didn't see her either in heat after the first time. I wanna mate her, what should I do?
Answer: There are several ways to detect a heat cycle. One of them, is having access to a male dog that you can keep in the home, he'll know best, but of course, not everyone can do this. Another option is having vaginal cytology tests done to see where her hormones stand. Because breeding dogs requires a good amount of knowledge, I recommend that all prospective dog breeders find a breeding mentor who specializes in the selected breed and who can provide guidance and assistance to ensure all goes well as planned.
Question: Is it normal for my male Pit Bull to be in heat while my female is not?
Answer: Male dogs don't go into heat. Male dogs reach sexual maturity and then become interested in female dogs when they give off special pheromones that inform them that they are in or nearing the receptive stage of their heat cycle. Most likely, your female is nearing the stage where your male dog is interested, but she is not ready. She should become more and more receptive (in standing heat) in the next few days to a week.
Question: What If I miss breeding my Chihuahua when she's in heat? How long will I have wait for the next heat?
Answer: On average expect a Chihuahua to go into heat around every 6 months. Here is more info on the Chihuahua heat cycle: https://pethelpful.com/dogs/How-to-Breed-Chihuahua...
© 2013 Adrienne Farricelli
Chad on September 03, 2020:
May dog is a sibirian husky it been 2 years and we still didnt notice any sign of heat. Every day we always check if there is sign of heat we also let our male dog to smell her but my male look like not interested.
Navjot Singh on August 31, 2020:
I can't know exact age of my French bulldog female I think she is about 10 or 1 year she bleed for two days 2 or 3 times per day but she bleed with her washroom only did it mean that she is been in heat or not
Gambino on July 29, 2020:
Can a male smell a silent heat
email@example.com on July 02, 2020:
My dog has given birth for 6 puppies after that , it doesn't come for heat so please give a suggestions for her periods ( heat )
Dawn on July 01, 2020:
Hello my female is 10.5 months old. She had not come into heat yet. I am a breeder and she Ahmad recently been around three females in heat. The last couple of days my males are interested in her and even trying to mount her. There has been no blood. And no there is no way I missed it. I wipe her everyday. What is going on?
Tara on June 21, 2020:
Hi! I’m super confused about my dog’s heat. She’s a 10 month old Lhasa Apso and she’s yet to be on heat but today, she has a swollen vulva but no bloody discharge. What can I do,please?
Gaby on April 03, 2020:
I have a one year old female chihuahua and she's only been in heat once and I don't know if I should be worried because she is 2 months late, is that normal or should I be concerned?
My girl is showing signs of going into heat, but not bleeding. on March 26, 2020:
Her vaula is enlarged, licking & our desexed chihuahua is continuously humping her. But there’s no blood. We have our stud coming Sunday, but were confused on it’ll even work. Last time he was over she was bleeding abit, but they didn’t do a proper tie, hence why she didn’t get pregnant. Thank you.
Maureen on February 09, 2020:
My terrier had a litter of pups christmas 2018 and no sign of coming in season yet I am concerned as I was hoping to breed her and keep a puppy myself is there anything I can do
Shirley on January 05, 2020:
My retriever has been having heat cycles Every 8 months this time we are 9 months and nothing except moody and dogs constantly wNteing to mount her over the last few days could this be a silent heat ?
Greatness on December 12, 2019:
My dog (German shepherd) is 1 year and i have not even seen a sign of heat i assume she is on silent heat what should i do
Aly on October 02, 2019:
My dog is 3 weeks late should i consider taking her to a vet and checking for a silent heat?
Rhema Coker on September 13, 2019:
How do I know the symptoms when my dog is into a silent heat
Bonita on August 11, 2019:
My female pug has had 2 dry heats in a row is that normal
ted loftin nobles on June 02, 2019:
I have a two year old Aussie. She has been in heat as expected in the past. I was planning to breed her during her heat cycle that was due in April. As of yet, she has not come into heat ! I am getting worried about this. Is it possible that she's just late?
Darshita on May 31, 2019:
I have a Pomeranian female 2 yrs and she’s going under silent heat for the 3rd time and swelling is not proper at all. I am trying to mate her as she’s not having enough swelling because of silent heat. Is there any remedy or treatment to increase her heat or to make her heat proper?
Alissa C on May 08, 2019:
I have an almost 18 month old Morkie and no signs of heat... have an older yorkie make that is fixed but concerned my little girl hasn’t come into heat yet. Is that normal...?
Sneha on April 13, 2019:
Hi my labroader is 16 months old and not once have I noticed she’s gotten her heat. I’m very worried on why she hasn’t gotten her first heat. Please suggest me what can i do
RiffRaffMama on April 09, 2019:
@Winona Siedentopf - yes she could become pregnant if she is having a heat cycle, no matter how young she is. Obviously having her fall pregnant at such a young age would be disasterous as her body is not mature enough to properly grow the puppies and she is far too small to birth them, which can cause miscarriage or at worst, death. So keep her protected from male dogs or get her desexed.
Winona Siedentopf on March 21, 2019:
My 4 month old puppy showed all the systoms of being in heat. Even driving my male nuts. But she did not bleed. I need to know if she could still become pregnant without bleeding if my male made contact?
daniel on March 04, 2019:
How many times does a dog have to mount in order for her to get pregnant specifically a border collie male and female
Deanna on January 11, 2019:
Helpp, 2 days ago my dog left a huge pile of bloody discharge and since then weve been waiting for it to happen again assuming shes in heat. We havent seen anymore blood and her nipples and privates arent swollen like i read about. Should i be concerned? Only other signsof heat i see is agression
sandra mcpherson on January 09, 2019:
If female dogs go into heat at around the same time.Can it work the opposite? Another female in the house that is fixed, can delay heat on the other female...
Bernice on December 30, 2018:
Hi my French Bulldog is 17 months old and not once have I noticed she’s gotten her heat. I’m very worried on why she hasn’t gotten her first heat. Maybe she got a silent recently my male dog has been have sexual behaviors towards her and follows her around but I don’t see no sign of heat coming. What could this all be ? Thank you.
Charlotte on October 03, 2018:
My dog is 6 years old and she has never bleed.
Dude on June 27, 2018:
What if there was no blood but a gooey kind of clear kinda green discharge what does that mean.