Animal Health
February 11, 2005
PseudoPregnancy (Pseudocyesis)

Many dog owners locally have suffered the disappointment of expecting puppies from their dogs after what may be considered a successful mating. This condition may have resulted from what is called a pseudo-pregnancy.{{more}}

Pseudo-Pregnancy, meaning false pregnancy is a reproductive problem that some mature female dogs may experience more than once during their reproductive life.

During the occurrence of false pregnancy, the dog or dogs will normally manifest all the visible signs of pregnancy such as severe development of the abdominal area, swollen vulva, increase in body weight and development of the mammary gland. However, at the end of 60-64 days there is no appearance of puppies.

Personally, I know many dog owners who have had such an experience more than once.

The reason for such a manifestation during a false pregnancy is the prolonged activity of the Corpus Luteum. The Corpus Luteum is the structure which forms in the ovary after ovulation and conception. This Corpus Luteum is responsible for the sustenance of the pregnancy.

The question is why is there a Corpus Luteum if there is no conception? The answer to such a question is not fully known. However, it is believed that abnormal hormone production may be responsible for the formation of the Corpus Luteum and thus false pregnancy.