False pregnancy, most commonly termed pseudocyesis in humans and pseudopregnancy in other mammals, is the appearance of clinical and/or subclinical signs and symptoms associated with pregnancy when the person or animal is not pregnant. Clinically, false pregnancy is most common in veterinary medicine (particularly in dogs and mice). False pregnancy in humans is less common, and may sometimes be purely psychological.
In humans (pseudocyesis)
Cases of pseudocyesis have been documented since antiquity. Hippocrates gives us the first written account around 300 B.C. when he recorded 12 cases of women with the disorder. Mary I (1516-1558), Queen of England, was perhaps the most famous of western historical examples, who believed on several occasions that she was pregnant, when she was in fact not. Some even attribute the violence that gave her the nickname “Bloody Mary” to be a reaction to her disappointment on realising she was without child. Other medical historians believe that the queen’s physicians mistook fibroid tumors in her uterus for a pregnancy. John Mason Good coined the term pseudocyesis from the Greek words pseudes (false) and kyesis (pregnancy) in 1923.
More recently, pseudocyesis has received attention in popular culture. It has been featured in the television shows CSI: Crime Scene Investigation, Law and Order SVU, The Simpsons, Shameless, General Hospital: Night Shift, and Grey’s Anatomy, in the films Who’s Afraid of Virginia Woolf? and Oldboy, and on the Kaleidoscope album White Faced Lady.
Signs and symptoms
The symptoms of pseudocyesis are similar to the symptoms of true pregnancy and are often hard to distinguish from it. Such natural signs as amenorrhoea, morning sickness, tender breasts, and weight gain may all be present. Many health care professionals can be deceived by the symptoms associated with pseudocyesis. Research shows that 18% of women with pseudocyesis were at one time diagnosed as pregnant by medical professionals.
The hallmark sign of pseudocyesis that is common to all cases is that the affected patient is convinced that she is pregnant. Abdominal distension is the most common physical symptom of pseudocyesis (60– 90%). The abdomen expands in the same manner as it does during pregnancy, so that the affected woman looks pregnant. This phenomenon is thought to be caused by buildup of gas, fat, feces, or urine. These symptoms often resolve under general anesthesia and the woman’s abdomen returns to its normal size.
The second most common physical sign of pseudocyesis is menstrual irregularity (50–90%). Women are also reported to experience the sensation of fetal movements known as quickening, even though there is no fetus present (50%-75%). Other common signs and symptoms include gastrointestinal symptoms, breast changes or secretions, labor pains, uterine enlargement, and softening of the cervix. One percent of women eventually experience false labor.
To be diagnosed as true pseudocyesis, the woman must actually believe that she is pregnant. When a woman intentionally and consciously feigns pregnancy, it is termed a simulated pregnancy.
There are various explanations, none of which is universally accepted. Psychodynamic theories attribute the false pregnancy to emotional conflict. It is thought that an intense desire to become pregnant, or an intense fear of becoming pregnant, can create internal conflicts and changes in the endocrine system, which may explain some of the symptoms of pseudocyesis. Another theory concerns wish-fulfillment. It holds that if a woman desires pregnancy badly enough she may interpret minor changes in her body as signs of pregnancy. Proposed biological mechanisms include the effect of stress on the hypothalamo-pituitary-adrenal axis, constipation, weight gain and the movement of intestinal gas.