Female dogs undergo alternate periods of 'heat' and quiescence after every 8 to 9 months. The heat period is called estrus cycle and is characterized by increased sexual urge. During estrus period the female dog is at her most fertile state as she ovulates and also shows some signs of heat. The diestrus period follows next, in which the female gets impregnated and undergoes hormonal changes to prepare the body for pregnancy. However, sometimes this usual cycle is disrupted and the female undergoes a condition called pseudocyesis, which is nothing but false pregnancy.

Causes

The exact cause of false pregnancy in dogs is not known. However, this condition can be traced back to the time when dogs used to live in packs. During that time, all the females in the pack used to come in heat, but only the alpha female got to mate with the male. Remaining females would still exhibit some of the pregnancy symptoms and would even lactate. This allowed them to nurse the offspring produced by the alpha female.

Technically speaking, hormonal imbalance is supposedly associated with this condition. When there is excess of prolactin and less of progesterone, the dog exhibits some unusual symptoms. False pregnancy is evident if the dog has not been mated in 8 to 12 weeks after estrus and yet exhibits symptoms akin to pregnancy. Oftentimes, the female has such strong nurturing instincts that the body is tricked into believing that she is actually pregnant. If you are sure that your dog has not been fertilized and yet looks as though she is pregnant, then you should probably look for the signs and symptoms of false pregnancy.

Signs and Symptoms

Symptoms of false pregnancy can be found at physical as well as emotional level. Some of the physical signs include:

The most obvious symptom of false pregnancy is enlarged mammary glands. The teats also swell and become tender.
Oftentimes, the dog may even secrete milk or colostrum. Other symptoms include abdominal swelling and vaginal discharge.
Although, the abdomen does not swell as much as during a real pregnancy, it sure swells to some extent.
The dog may also suffer from morning sickness with occasional bouts of nausea and vomiting. During this period, the dog may exhibit some unusual inclination towards food. Blander food is preferred over usual dog food.
She may have increased appetite with frequent hunger pangs. Conversely, she may go on for days without touching food.
Other pregnancy symptoms such as fatigue, increased urination are also common.

This period can be extremely stressful for your dog. You can pick up subtle signs from her behavior such as those given below.

She exhibits strong maternal instincts by becoming emotionally attached to certain objects like toys, shoes, etc.
She becomes overtly possessive of soft toys, which she treats as her puppies.
She also shows a nesting behavior by dragging papers and blankets to a secluded corner in the house where she intends to build her nest.
She cares for her 'puppies' in this nest and becomes overprotective.

However, this state may cause a lot of confusion and disorientation in her, as she continues to think she is pregnant but there are no real puppies to care for. She secretes milk for her puppies but there are no puppies to suckle on. The absence of puppies can be emotionally challenging for her.

Diagnosing False Pregnancy

False pregnancy in dogs can be diagnosed by a vet through stomach palpation. He examines the stomach of the dog to check if she is really pregnant or not. However, this is not the most reliable method of diagnosing since one cannot feel the presence of puppies in the early state of pregnancy. An ultrasound or X-ray is more reliable in detecting false pregnancies. Some experienced owners can also detect false pregnancies on their own by studying the physical and emotional changes in the dog. False pregnancies tend to reoccur, hence dogs with a history of false pregnancies are easiest to diagnose.

Treatment

The symptoms of false pregnancy subside on their own within 2 to 3 weeks. During this period it is important to keep your dog's behavior in check. Licking mammary glands may lead to even more lactation, hence prevent your dog from doing so. Some vets advise to cut food intake in order to reduce milk production. Some drugs can be used to reduce the milk production, however they are not recommended, for they can cause side effects. Besides, sedatives can be used if the dog shows an uncontrolled aggressive behavior.

False pregnancy is pretty common in dogs and there is nothing to worry about that. However, if there are no physical symptoms other than enlarged glands, then you should consult a vet, as it may be due to some underlying medical condition.