Phantom pregnancies in dogs are very common, with symptoms from mothering behaviour and lactation, to lethargy and vomiting. Find out more about signs, causes and possible treatment.
Has your dog started acting like they are pregnant, mothering their toys and creating a nesting space? Have you noticed mammary development and even milk from their nipples? Some female dogs may display signs equivalent to morning sickness; with lethargy and vomiting. If your dog has not been mated, this may leave you scratching your head as to why they appear pregnant. If they have been mated, before you get too excited about visions of cute puppies, you need to make sure it’s not a false or phantom pregnancy.
Read on to discover what the signs are, how a false pregnancy gets diagnosed and when medical treatment is necessary.
What causes phantom pregnancy in dogs?
The origins of phantom pregnancy are thought to be due to the pack behaviour of our domestic dog’s ancestors. All the females in the pack help to rear the family pups and feel motherly towards them, even when they are not their own offspring. This cooperative behaviour is driven by hormones. After a female dog has a season, she experiences a prolonged peak of the ‘pregnancy hormone’ progesterone lasting 8-9 weeks, whether she is pregnant or not (this does not occur in humans). As levels of progesterone decline levels of a second hormone, prolactin, increase. This is what triggers the physical and psychological symptoms of pregnancy. In some dogs this may be mild – not enough to notice – but in others the symptoms can be very convincing to both the dog and her owner.
What are the symptoms of a false pregnancy?
A dog can display a range of symptoms. These can be grouped together in physical changes and uncharacteristic behaviours.
The signs of false pregnancy are usually seen 4-8 weeks after a season. Researchers from Glasgow vet school (Root and others) published a helpful review from the experiences of almost 400 vets in 2018. They found that the most common finding was enlargement of the mammary glands (breasts). Clear fluid brownish fluid or milk may be produced by the swollen glands.
Most female dogs who show symptoms will be restless and anxious, unsettled by the change in hormones. They often eat less and are less keen to interact with people and go for walks. Rarely, they vomit and their abdomens appear swollen.
Along with these physical changes, behavioural changes are common. Usually, the dog will act as if she has had pups. She may collect soft toys, cushions, shoes, socks or other objects from around the house and take them to her bed or a chosen corner. She will then mother them: hide them, guard them and lick them.
At this time, she may become aggressive and protective of her nest and imaginary babies. It is important not to misunderstand her at this point. She honestly believes these are pups so it is best to distract her with walks and cuddles when possible, rather than try to encourage her to give them up. She is likely to become uncharacteristically aggressive if she feels the safety of her pups is in question. Even the sweetest family pet can growl and even bite in this situation.
It is believed by some behaviourists that if a dog is spayed when she is experiencing false pregnancy, she may behave more aggressively. This is why vets tend to advise spaying a reasonable time after a season.
Phantom pregnancy after spay – dog producing milk. Advice and treatment
False pregnancy is most commonly seen in female dogs (although cats may rarely be affected). Hormone changes after a ‘season’ or heat convince her and her body that she is pregnant. It is sometimes called phantom pregnancy or pseudopregnancy. The hormone changes that cause false pregnancy are normal in the dog but sometimes the symptoms get out of hand and are distressing for the dog and her owners.