If your dog becomes pregnant, you will likely wonder how long the pregnancy will last. This article is going to explore the answers right here. What you should know right away is that the answer is not exact — no two dogs will have the same pregnancy — but just like with human pregnancies, hundreds of years of study and experience have taught us a pretty specific timeline to follow.
It is more a well-informed estimate than an exact schedule, however, and should be treated as such. That being said, below you’ll see just how long a dog pregnancy lasts.
How to Tell if Your Dog is Pregnant
It’s actually not as easy to tell if a dog is pregnant than it is for humans. We have take-home tests that will tell us instantly if we are expecting, but it is likely that you will need to take your dog to see your veterinarian to determine a pregnancy.
You should come armed with information, such as the exact date your dog was bred, or best estimate if you are unsure because all dog pregnancy testing methods are time sensitive.
There are four common methods used by veterinarians to determine if a dog is pregnant:
- Hormone tests
The best way to determine if your dog is pregnant early on in gestation is via an ultrasound. An ultrasound will not only detect whether or not your dog is pregnant but will also be able to determine if the fetus is alive by listening for fetal heartbeats. The ultrasound can also help calculate the gestational age of the fetus, and rule out other causes of uterine distension, such as a pyometra (canine bacterial infection). Veterinarians recommend that you take your dog in for an ultrasound between 25 and 35 days after mating.
A palpation is the most convenient and cheapest way to diagnose a canine pregnancy. Palpation simply involves using your hands to check the dog’s body for a fetus. Each fetus has a membrane around it that will grow to form a fluid-filled sac.
Between weeks three and five (days 21 and 35) of gestation, these will grow to roughly the size of a ping pong ball in a medium-sized dog (around 45 pounds). These sacs can be felt in the dog’s stomach but will lose their shape after around one month.
While also good for determining a pregnancy, an X-ray is a more reliable way for breeders and veterinarians to determine how many puppies they can expect from their litter. Thus, the X-ray will be more effective later in a pregnancy, since the fetus’ skeleton won’t be fully formed until days 42 to 45. If you wait until after day 55, the veterinarian should be able to give you an accurate count of the expected number of puppies.
Hormone tests can also be used to determine if a dog is pregnant. In these tests, veterinarians will look for a hormone called relaxin. A pregnancy is the only time relaxin is released from placental tissue. This makes hormone testing reliable for determining a pregnancy, however, the dog must be at least 30 days into her gestation in order to produce accurate results. Testing too early can produce a false negative.
Getting an accurate diagnosis is the first step, but once you know your dog is pregnant, it helps to understand the canine reproductive cycle before you can reach an answer to the “how long is a dog pregnant?” question.
The Canine Reproductive Cycle
A female dog’s heat cycle comes along with its own set of stages which breeds use to determine the best time to breed their dogs. Female dogs will go into heat roughly every six months, although this may vary slightly depending on the breed and the individual dog.
A dog’s reproductive (heat) cycle will typically last 18 to 21 days and occurs in four stages. These stages are:
This first stage of a dog’s heat cycle lasts roughly nine days. During proestrus, females will begin to attract males, but will actually reject them until stage two. Signs of proestrus that you may notice include a bloody discharge and/or a swelling of the vulva.
Lasting anywhere from three-to-four days to seven-to-11 days, the estrus stage is when a female dog is receptive to the male. Breeders often have their veterinarian take vaginal smears and blood tests during this stage to breed their dogs at the perfect time. During estrus, your dog may exhibit a soft and enlarged vulva. Their bloody discharge should decrease and become lighter in color.
Technically the final stage of the reproductive cycle, diestrus usually occurs around day 14. During this time, the dog will no longer be receptive to the male, and the heat cycle will be complete. The discharge will become redder once more, then taper off, and the vulva will return to normal. You will know the heat cycle is complete when there is no longer any discharge and the swelling has subsided.
Anestrus is the period of time between the end of one heat cycle and the start of the next. This phase typically lasts around six months.
Being able to understand a dog’s heat cycle will help you to not only determine your dog’s optimal breeding time but also to learn the length of a dog’s pregnancy. By keeping track of your dog’s heat cycle and breeding time, you will likely be able to calculate at least a close range of your dog’s conception date. This will help your veterinarians when they test your dog for pregnancy.
How Long is a Dog Pregnant?
If you are considering breeding your dog, you will need to know for how long the dog will be pregnant, know as its gestation period. Having this knowledge will be extremely important to help you plan for checkups at your veterinarian, management of the different stages of your dog’s pregnancy, prepare you for any potential issues or emergencies, and of course, get you ready for the birth of an adorable litter of puppies.
The typical duration for a full-length canine pregnancy is about 63 days, although this can vary depending on the dog as well as its breed. Although a dog’s pregnancy happens rather quickly, it will be nearly impossible to tell if your dog is pregnant during the first few weeks of its pregnancy, and you can carry on with normal feeding and exercise during this time.
A pregnancy can be seen on an ultrasound as early as 25 days after fertilization, but it won’t be until 42 days in that the puppies’ skeletons will calcify. Until this occurs, the puppies cannot be confirmed via X-ray. This is also the earliest a vet can feel the puppies in the uterus.
The gestation period can vary for a few reasons. First, sperm can actually live inside the female for several days, and the eggs will remain fertile for up to 48 hours. This means the act of mating is not actually the exact measurement of gestation, because it might occur up to two days later. This is why you will need to see your veterinarian to get a better estimate of gestation.
While ultrasounds are the most common tests, hormone measurements will produce a more exact timeframe for the pregnancy. Breeders often use vaginal smears and blood tests to monitor the dog’s reproductive hormones to find the optimal time for breeding, which can also assist in measuring the length of the pregnancy and creating a possible due date.
According to accurate hormone measurements, dog pregnancy length can be as follows:
- 56 to 58 days from day one of the diestrus stage of the dog’s reproductive cycle (see above)
- 64 to 66 days from the initial rise in progesterone (an important hormone in the reproductive process)
- 58 to 72 days from the first breeding session
Since a dog’s pregnancy is short compared to humans, lasting roughly nine weeks, it means that things move quickly and it will be important to manage your dog’s health during each stage of the pregnancy.
Dog Pregnancy Stages
See our week-by-week guide on dog pregnancy stages for a full review on what to expect during your dog’s pregnancy, but here is a quick recap.
The embryos will travel to the uterine horns by the end of the first week and will embed in the uterine lining by around day 16. By day 22, the fetus will begin to take shape, and your veterinarian should be able to detect fetal heartbeats on an ultrasound by day 28 to 30.
Most dogs will not show any visible symptoms during this first month of pregnancy, and you should continue to carry on with their routine as usual. Some signs of dog pregnancy to watch out for include an increased appetite, slightly enlarged nipples, becoming more affectionate, a clear vaginal discharge appearing toward the end of the first month, and some morning sickness and decreased physical activity.
Things really pick up the pace during the second month of your dog’s pregnancy. The fur, claws, and skeleton will all be visible by around day 45, and an X-ray on day 50 should be able to reveal the number of puppies in the litter. By the end of the month, your pregnant dog will begin to look for a quiet place to nest.
During this month, you should notice an increased appetite at the start of the month, which will taper down toward the middle. You should see a significant weight gain and an enlarged abdomen, increased urination, and vaginal discharge. You may also be able to see puppies move in your pregnant dog’s abdomen.