Issue Description Pseudocyesis is the medical term for a false
pregnancy. Pseudocyesis can cause many of the signs and symptoms of
pregnancy, and often resembles the condition in every way except for
the presence of a fetus. Other Names Pseudocyesis, Phantom Pregnancy, False Pregnancy
Causes Dogs become pseudopregnant following an estrus
phase in which the female dog is not bred, or in which it is bred by
an infertile male. Most species require signals from an embryo (such
as IFN-�„ in ruminants) to alert the female's body of a pregnancy.
This maternal recognition of pregnancy will cause persistence of the
corpus luteum and the development of characteristics and behaviors
necessary to care for offspring. Limited research suggests that
progesterone secretion is similar in pregnant and non-pregnant
bitches, so veterinary researchers hypothesize that dogs may not
require molecular factors from the embryo for maternal recognition of
pregnancy, and instead the corpus luteum persists regardless of
pregnancy. Since the corpus luteum is not degraded, it will cause the
development of maternal characteristics in the absence of pregnancy.
Pseudopregnant bitches will develop their mammary glands, lactate, and
build nests to varying degrees depending on breed. Although bitches
usually only cycle once (monestrous bitches) or twice (diestrous
bitches) per year, pseudopregnancy in dogs is common because the bitch
does not have to be bred to become pseudopregnant.
Symptoms Many dogs whether they are bred or not, will
develop a false pregnancy, and look, act, and even think as if they
are pregnant. Some will carry small toys or pillows around and even
start digging a nesting site wherever they please. When it is about
the same time in which they would be delivering the puppies, usually
63 days after a mating, milk will come out on its own from the mammary
glands. Some dogs become distressed because they cannot find the
puppies they psychologically feel they should be nursing.
Diagnosis The diagnosis of false pregnancy is made by a
history of a heat cycle (estrus) within the preceding 2 to 3 months of
presentation to the veterinarian and the clinical signs of pregnancy.
A physical examination will be done; the veterinarian will feel the
abdomen (palpation). The veterinarian may want to take radiographs
(X-rays) or perform ultrasound (visualization of deep body structures
by ultrasonic waves) to rule out normal pregnancy or infection of the
uterus as a cause of the signs.
Treatment In most animals, no treatment is necessary,
because the affected female will "cycle" out of the false pregnancy on
her own. This may take as long as 2 months. Surgical removal of the
ovaries and uterus (spaying) may be advisable in females that have
severe or repeated false pregnancies. If your pet's mammary glands
become large and painful, application of alternating warm and cold
compresses 3 to 4 times daily usually relieves the discomfort. You can
also feed one half the normal amount of food for 2 days to reduce milk
production. If she is still having pain after 2 days, contact your
veterinarian. Also notify your veterinarian if there is discharge of
blood or fluid from your pet's vagina or if she is depressed for more
than 2 days.
Spay During False Pregnancy It might seem like a good idea to spay the
female to end the false pregnancy as spaying will remove the ovaries
and the corpora lutea they carry. Unfortunately, this does not end the
prolactin production from the pituitary gland so spaying may actually
prolong the false pregnancy. It is best to wait until the false
pregnancy is over and then spay her to prevent future episodes.