What Are False Pregnancies in Dogs?

Medically Reviewed by Kathleen Claussen, DVM on December 05, 2021
4 min read

False pregnancy is a common condition in unneutered female dogs. It’s also known as pseudopregnancy, pseudocyesis, or a phantom pregnancy in dogs.   

Around 80% of unspayed female dogs — those who still have their ovaries and uterus — will show some signs of a false pregnancy at least once in their lives. Around 67% will have recurring symptoms. 

False pregnancies begin around 45 to 60 days after your dog’s last estrus cycle — also known as heat — and mimic many of the symptoms of a true pregnancy.

False pregnancies can last anywhere from one week to one month. The symptoms can begin at any age or after any given estrus cycle. Your dog may not experience a false pregnancy after every single cycle, though. 

False pregnancy in dogs is caused by normal hormonal changes that begin after every estrus cycle. The purpose of this change is to prepare your dog’s body for pregnancy. Sometimes, though, these changes progress even when your dog isn’t pregnant. 

The levels of a hormone called progesterone are high when your dog is ovulating — during heat — and begin to taper off around six or more weeks later. This decrease in progesterone leads to increased levels of a different hormone: prolactin. High levels of prolactin cause many of the symptoms of false pregnancy.  

Phantom pregnancy can also be caused by spaying your dog too soon after an estrus cycle. The removal of the ovaries changes hormone levels at a problematic time in your dog’s cycle — leading to the symptoms of false pregnancy. It’s best to wait at least eight to ten weeks after your dog was last in heat before spaying her. Depending on the breed, dogs go into heat 1-3 times per year. 

The symptoms of false pregnancy are very similar to both the physical and behavioral changes that happen to a dog that’s actually pregnant. Symptoms may intensify with each estrus cycle. 

Physical symptoms include: 

  • Depression
  • Lethargy
  • Loss of appetite 
  • Swollen mammary glands 
  • Milk production 
  • Fluid retention
  • Signs of false labor 
  • A swollen belly

Behavioral changes include: 

  • Nesting — around 66% of dogs with false pregnancies gather many of their toys in an area and become protective of that spot. 
  • Over-protectiveness of toys — around 54% of dogs with false pregnancies will guard and constantly carry around particular toys.
  • Aggression
  • Attempting to self-nurse

If this is your dog’s first time showing signs of a false pregnancy, you should take her to the vet to rule out a real pregnancy or a more serious condition. 

You should also see your vet if the symptoms last longer than eight weeks. This may be a sign of liver dysfunction or hypothyroidism — other conditions that alter your dog’s hormone levels.  

False pregnancy in dogs is not dangerous. In fact, they’re considered to be a fairly normal feature of the female dog hormone cycle. 

One theory about why female dogs frequently go through cycles of pseudopregnancy is that the behavior was helpful when dogs lived in packs. With pseudopregnancy, there were available females that didn’t have their own pups but could still provide protection and even milk to the pack’s puppies.

At present, there aren’t any increased risks for other diseases or conditions that are associated with false pregnancies. 

Usually, your dog won’t need any treatment for the false pregnancy. The symptoms should clear up on their own within a month. 

The most effective long-term treatment is to spay your dog. This is the process of surgically removing your dog’s uterus and ovaries. Removing these organs stops your dog’s estrus cycles and will keep all false pregnancies from happening. Spaying also has the added advantage of preventing mammary gland cancer and deadly uterine infections. 

If your dog’s mammary glands are swollen and producing milk, it will help to leave them alone and not stroke or bathe them — this will only stimulate them more and make symptoms last longer. 

You can also help your dog deal with her behavioral changes by removing toys and preventing her from self-nursing. Sometimes, cones or Elizabethan Collars can help with this. 

Occasionally, medicines can help relieve symptoms. For example, diuretics can help with fluid retention and tranquilizers with anxiety.  

There are also methods that can be used to directly alter your dog’s hormone levels. Specific prescriptions — like cabergoline — can reduce the effects of the hormone prolactin in your dog’s body and help reduce the symptoms of false pregnancy, but this treatment is generally considered excessive. It’s less commonly prescribed than other treatments.