Do Dogs Look Pregnant After Heat?

What Happens During a Dog’s Heat Cycle

Dogs go through a regular reproductive cycle called an estrus cycle, more commonly known as a “heat cycle.” Females experience these cycles roughly twice a year until they are spayed, with the length and frequency varying between breeds. There are four distinct stages of the canine estrus cycle:

Proestrus – This initial stage lasts 5-10 days. The vulva begins to swell and bleed lightly. While females will allow males to mount during this time, they are not yet fertile and will not allow full mating. This stage is driven by rising estrogen.

Estrus – Also known as the “fertile” or “receptive” period, this phase lasts 5-10 days. The vulva remains swollen and the female will now accept mating. Ovulation occurs towards the end of this stage, with fertility lasting 48-72 hours. This stage is influenced by estrogen and progesterone.

Diestrus – After ovulation, progesterone levels rise and estrogen drops off. This stage lasts 60-90 days in a pregnant female as the fertilized eggs implant and develop. In non-pregnant dogs, it lasts 60-100 days as the uterine lining is reabsorbed. The vulva returns to normal size.

Anestrus – This quiet stage has no sexual activity. It lasts 4-5 months as hormone levels remain low in preparation for the next cycle. Most dogs experience anestrus in the fall and winter.

Physical Changes During Heat

When a female dog enters her heat cycle, known as estrus, her body undergoes some noticeable physical changes. The most obvious sign is swelling of the vulva, the external female genitalia. According to The Spruce Pets, “The vulva will swell up and become softer, pinker, and more pronounced.”

Along with vulvar swelling, vaginal bleeding is another telltale sign of heat in dogs. As explained by PDSA, “Signs of a heat include a swollen vulva (private parts), bleeding, and changes in behaviour.” The vaginal discharge is often bloody at first but then becomes watery and straw-colored near the end of the heat cycle.

In addition to the vulvar and vaginal changes, female dogs in heat may exhibit behavioral shifts as well. They tend to become more affectionate, playful, easily distracted, and may urinate more frequently. These are all natural responses as the dog’s body prepares for potential mating and pregnancy.

Male dogs will also be attracted to a female in heat and may exhibit their own behavioral changes. According to YourPetandYou from Elanco, increased licking of the vaginal area is another physical sign of estrus in dogs.

In summary, the characteristic signs of a female dog in heat are swollen vulva, vaginal bleeding, and behavioral changes. Being able to recognize these changes is important for pet owners to manage their dog’s heat cycle properly.

Can Dogs Get Pregnant During Heat?

Yes, dogs can become pregnant during their heat cycle, which is also known as estrus. According to the AKC, the most fertile point is usually around 9-10 days after the heat cycle starts, which is when ovulation typically occurs 1. However, dogs can get pregnant for a few days before and after ovulation as sperm can survive for up to a week inside the female dog’s reproductive tract waiting for the eggs to be released.

The heat cycle lasts around 2-4 weeks and happens about twice a year starting from 6 months old until a dog is spayed 2. During this time, the dog’s body is preparing for pregnancy and fertilization. When the eggs are released from the ovaries into the fallopian tubes, this is called ovulation. If sperm are present due to mating, the eggs can get fertilized in the oviducts and embed in the uterine lining, resulting in pregnancy. Therefore, the fertility window spans a number of days surrounding ovulation when the female dog can get pregnant if breeding occurs.


Some dogs exhibit pregnancy-like symptoms after heat that can look like pregnancy but are not caused by an actual pregnancy. This is known as pseudopregnancy or false pregnancy. According to the VCAAnimal Hospitals, pseudopregnancy happens when “the ovaries produce progesterone, as if the dog were pregnant, even though she is not.” The hormone changes after heat can cause the female dog’s body to behave as if she is expecting puppies, even when no mating has occurred.

Pseudopregnancy often occurs 4-9 weeks after the female dog goes into heat. Some of the most common signs of pseudopregnancy mirror those of true pregnancy and include abdominal enlargement or distention, milk production, nesting behaviors, and mothering of toys or other objects. However, there are no actual fetuses or pregnancy. Veterinarians can confirm pseudopregnancy in dogs through abdominal palpation showing no puppies in the uterus.

Signs of Pregnancy

There are several signs that may indicate a dog is pregnant after going into heat. These include:

  • Enlarged or pink nipples – The nipples will begin to enlarge and become pinker in color around 3-4 weeks after conception as the dog’s body prepares for nursing the puppies. The area around the nipples will also swell.
  • Weight gain – Dogs will gain weight steadily if pregnant, usually starting around the 4th week of pregnancy as the fetuses begin to grow. A pregnant dog’s weight gain is usually between 25-50%.
  • Increased appetite – With the demands of pregnancy and nursing, pregnant dogs need to take in more calories. You may notice an increase in your dog’s appetite around the 3rd or 4th week of pregnancy.
  • Nesting behavior – Close to delivery, pregnant dogs may exhibit nesting behaviors like shredding bedding and paper and rearranging their space.

According to the AKC[1], these are some of the most obvious signs of dog pregnancy. If you notice any of these, your dog may be expecting puppies. However, some of these signs can also occur with pseudopregnancy, a false pregnancy. So it’s important to watch for other signs of pregnancy as well before determining if your dog is definitely expecting pups.


Differences Between Pseudopregnancy and Real Pregnancy

There are some key differences between a pseudopregnancy and a real pregnancy in dogs that can help determine which one your dog is experiencing:

  • Duration – The signs of pseudopregnancy usually resolve within 2-3 weeks from the onset. A real pregnancy will continue to progress over the typical 63 day gestation period.Pseudopregnancy vs real pregnancy in dogs treatment.

  • Weight gain from mammary enlargement and fluid production is temporary in pseudopregnancy. Weight gain continues steadily throughout a real pregnancy as the fetuses grow.Signs of false pregnancy in dogs

  • Physical changes like nipple enlargement and abdominal distension go away after pseudopregnancy ends. These changes persist in a pregnant dog due to fetal development. Is false pregnancy in dogs dangerous

  • Behavioral changes like nesting, mothering toys, and appetite fluctuations are temporary with pseudopregnancy. The hormones of pregnancy make these behaviors persist when a dog is truly pregnant.

If your dog is showing signs of pregnancy but they disappear after a few weeks, she may have had a false pregnancy. Persisting symptoms beyond 4-5 weeks likely indicate a real pregnancy, especially if mating was observed during her heat cycle.Pseudopregnancy vs real pregnancy in dogs symptoms

When to See the Vet

If you suspect your dog may be pregnant after her heat cycle, the best thing to do is have your vet confirm the pregnancy. There are a few different methods vets can use to detect pregnancy in dogs:

Physical Exam – Your vet can palpate your dog’s abdomen to feel for fetal growths starting around day 28-30 of gestation. However, it’s not always easy to count puppies or be 100% certain of pregnancy through palpation alone.

Ultrasound – An ultrasound can usually detect fetal heartbeats and confirm pregnancy starting around 25-35 days after breeding. This is one of the most accurate ways to diagnose a dog’s pregnancy.

X-rays – Abdominal x-rays can spot fetal skeletons starting around day 45 of gestation when bones begin to calcify. X-rays can give a puppy count and help determine how far along the pregnancy is.

Blood Tests – There are blood tests such as relaxin or pregnancy detection kits that can confirm pregnancy in dogs from day 22 onward. These tests detect pregnancy hormones in the bloodstream.

The best way to know for sure if your dog is expecting puppies is to take her to the vet if you notice signs of heat or suspect pregnancy after a heat cycle. An experienced vet can run tests and give you definitive answers regarding your dog’s pregnant state and health.

Caring for a Pregnant Dog

Proper care of a pregnant dog is essential to her health and the health of the unborn puppies. Here are some tips for caring for a pregnant dog:

Provide high-quality nutrition. Pregnant dogs need more calories, protein, calcium, and other nutrients. Talk to your vet about switching to a high-quality puppy food or a specially formulated diet for pregnant/nursing dogs. Feed her more frequently in smaller meals.

Allow moderate exercise. Going for gentle walks and light play is fine, but avoid strenuous exercise. Swimming is an excellent way to exercise without putting pressure on the joints.

Prepare a whelping box. This enclosed space allows the mother dog to nest and give birth comfortably. Line it with puppy pads, soft blankets, and include a pig rail so puppies don’t get smothered.

Reduce stress. Give your pregnant dog a quiet place to rest undisturbed. Interact gently, watch her body language, and give affection if welcomed.

Make regular vet visits. Your vet will monitor your dog’s pregnancy, give nutritional advice, and prepare you for the birth.

With the proper care, you can keep your pregnant dog happy, healthy, and ready to welcome her puppies. Consult your veterinarian if you have any concerns.

Spaying and Neutering

Spaying and neutering dogs provides many health and behavioral benefits. According to the AVMA, spaying female dogs prevents uterine infections and reduces the risk of breast cancer. Neutering males eliminates their risk for testicular cancer. The surgery also reduces the chance of prostate issues in males.

In addition, fixing dogs can curb undesirable behaviors associated with mating urges, like roaming, mounting, and aggression. According to the Mendocino County Animal Care Services, spaying before a female dog’s first heat offers the best protection from mammary tumors. Early spay/neuter avoids unwanted litters and may reduce health issues later in life.

While the procedure does have risks, spaying and neutering provides major benefits for a dog’s health and behavior over its lifetime. Pet owners should consult with their vet to determine the ideal time to spay or neuter based on their pet’s breed, size, and individual health profile.

In Conclusion

To summarize, a female dog’s heat cycle consists of four stages – proestrus, estrus, diestrus, and anestrus. While dogs can exhibit pseudopregnancy after their heat cycle, they can only get pregnant during the estrus stage when ovulation occurs. Some signs of pseudopregnancy include weight gain, enlarged nipples, nesting behaviors, and mothering toys. However, ultrasounds and blood tests are needed to definitively diagnose a real pregnancy.

If your dog mated during its heat cycle, monitor for signs of pregnancy or pseudopregnancy in the coming weeks. Seek veterinary care if you suspect pregnancy to properly care for your dog and the puppies. Spaying your dog is recommended to avoid unwanted litters in the future.

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