Dog Nipple Swelling After Heat Cycle: All You Wanted To Know And More!

When ready for conception, the female dog shows signs that they are in heat, such as a swollen nipple. But will my puppies nipples go back to normal after heat?

After consulting veterinarians and longtime pet owners, they gave us information about dog nipple swelling, its causes, and how to overcome the condition. Continue reading to learn more about a dog heat cycle and other causes of nipple swelling.

What Are Nipples or Mammary Gland Swelling In Dogs?

Nipple swelling in puppies is the proliferation or thickening of tissue or a lump in the breasts and the surrounding tissue. 

A dog’s mammary gland has two rows of subcutaneous glandular tissue around each nipple on either side of the female ventral surface.

The rows extend from near the underarms to the inguinal region near the genitals. There are five nipples on each row, and swelling can be in one or all of them. 

Swelling of a dog’s nipple is joint during or after the heat cycle, breastfeeding, and parturition.

A Dog’s Heat Cycle

Dogs undergo 4 phases in their heat cycle, namely:

1. Proestrus: The first phase is when she shows symptoms of coming in heat by swelling the vulva and bleeding.
2. Estrus: The second phase is when ovulation begins, preparing her to breed.
3. Diestrus:  At this phase, her body will start secreting more hormones in readiness to carry the pregnancy. Hormones levels will rise even if the dog isn’t pregnant, although she can’t conceive.
4. Anestrus: The final phase is when your dog’s body prepares for the next heat cycle.

The Common Symptoms That Your Dog Is On Heat Are:

• They roam in search of a partner by actively seeking the attention of a male dog.
• Increase in aggressive behavior. The dog becomes less social with people and tries to pick fights with unspayed females.
• It is swelling of the vulva and blood discharge.
• While in heat, the dog frequently licks its genitals to clean the discharge and relieve frustration.
• A dog on heat keeps her tail up while turning her butt toward other dogs indicating her readiness to mate, a behavior known as flagging.
• The swelling of the nipples is due to an increase in hormone levels. The nipples will swell when in heat and sometimes after ovulation.
• Frequent urination to disseminate pheromones to attract males.

Is It Normal For A Dog’s Nipples To Swell After The Heat Cycle?

During the heat cycle, a dog’s mammary glands and nipples don’t change in size. However, it’s common to see your puppy’s nipples and breasts swell as the heat cycle ends due to high progesterone levels.

Female dogs, when coming in season, may often lick their nipples and vulva out of frustration, causing them to swell.

If your dog is healthy and displays the common signs of being in heat, don’t worry when the nipples increase in size.

Why Are My Dog’s Nipples Swollen After Heat And She Isn’t Pregnant?

Has your unsprayed dog mated while in heat? If that is the case, she might be pregnant. Her body will start preparing for milk production, and you will see the nipples and breast swell.

However, pregnancy isn’t the only reason your dog’s nipple will swell. According to Garry England in the book Dog breeding, whelping.

In puppy care, 35 days after ovulation, when a dog’s heat cycle is over, there will be a noticeable increase in mammary gland size due to high levels of progesterone hormone secreted during ovulation and in the first half of the target pregnancy.

The veins around the nipples will also become more noticeable due to the increased blood supply to the breasts.

During a dog’s heat cycle, the nipples may enlarge because of other reasons like;

• Pregnancy
• Mammary hyperplasia
• Thyroid issues
• Infection
• Pseudo pregnancy
• Mastitis

If you notice that the swelling does not reduce, visit your vet for check up and management.

What Is Pseudopregnancy In Dogs?

Currently, there are not enough studies showing dogs’ causes of pseudopregnancies (fake pregnancies). Some biological theories relate them to a measure of increasing survival for wolf cubs.

The most common signs of pseudopregnancy in dogs are swollen nipples that are lactating. The dog will also change its behaviors during this time.

Signs that show your dog’s nipples are swelling due to pseudopregnancy.

• Nesting
• Mothering
• Protective over toys
• Lethargy
• Frequent water intake
• Aggression
• Loss of appetite
• Lack of interest in exercise
• Restlessness
• Swelling of the mammary glands, which may or may not have milk

Most dogs show part of these signs, and the severity will vary. Some dogs may exhibit severe symptoms, so you should take her to the vet.

How Long Do A Dog’s Nipples Stay Swollen After Heat?

So how long will my puppy’s nipples return to normal after the heat? And will they eventually return to normal?

If your dog’s nipples swell during or after the heat and she isn’t pregnant,  they will return to normal naturally. 

Expect the breasts and nipples to shrink to standard size within 2 – 3 weeks. The timeframe may vary, with some taking up to five weeks.

What Nipples Swelling Is Alarming For My Dog?

If your dog shows signs of severe nipple swelling with symptoms of infections or bleeding and she is constantly licking them, a visit to the vet is necessary.

There is no specific swelling size of nipples for a dog in heat, but if they affect the dog’s physical well-being or show infections and have an open wound, contact your vet.

 Does My Dog’s Swollen Nipples After Heat Require Medical Attention?

Is the puppy having swollen nipples in heat and acting healthy? Your dog goes through a regular cycle and doesn’t require specialized medical attention. It would help if you kept an eye on her well-being and behaviors. 

If not pregnant, the dog’s nipple should reduce to average size in a few weeks.

However, you need to consult the vet if there are some alarming symptoms with the nipple swelling. Some of the signs showing all do not well include:

• The swollen nipples are producing discharge or fluid
• A feel of lumps or masses under the nipple’s skin
• Loss of appetite
• Fever
• The dog experiences pain when you touch the mammary gland
• Evidence of physical injury on the nipples
• If your dog is unduly scratching and biting the nipples

However, if your dog looks healthy but the nipple swelling persists for a long time, seek a vet’s advice. 

The heat cycle might not contribute to the size increase, and your dog may be experiencing Pseudo pregnancy, has an infection, or has an allergic reaction due to some product or food.

Medical Interventions For Severely Swollen Nipples

Veterinarians will perform some tests and can prescribe some medication to reduce the swelling.

A cone can also help dogs that are constantly licking their nipples.

An elastic bandage may help heal, reduce milk production in pseudopregnancy, and prevent scratching.

Key Takeaways

• Swelling a dog’s nipples after heat is a routine biological body change, even if the dog isn’t pregnant. It occurs due to a high level of hormones in readiness for pregnancy.
• The swollen nipples will return to normal without medical intervention if the dog isn’t pregnant.
• In some cases, your puppy’s nipples will swell and show signs of milk if she has a phantom pregnancy.
• If your dog has mated and is pregnant, the mammary gland and nipples will continue increasing in size to enable breastfeeding.
• Consult a vet if your dog’s swollen nipples take longer to shrink back and show signs of infection.