06 December 2006

All the Signs of Pregnancy Except One: A Baby


Taken from the Science Times (New York Times) by ELIZABETH SVOBODA, 5 December 2006

Dr. John Radebaugh still vividly remembers his first professional comeuppance.

In the mid-1960s, Dr. Radebaugh, a young pediatrician, volunteered at a clinic for migrant farmworkers in Rochester, and one evening he got a call that a woman was in labor.

When he arrived at the scene, he found the woman with a melon-size stomach, groaning and writhing in pain.

“From the condition she was in, we thought she was going to deliver right then and there,” he recalled.

Dr. Radebaugh and the clinic workers who came with him decided to forgo a pelvic exam and drive the patient to a hospital emergency room posthaste. As he helped the woman into a wheelchair at the hospital, her water seemed to break, drenching him in clear fluid.

But when he called the hospital the next day to check on the patient’s progress, Dr. Radebaugh got an unexpected answer.

“Oh, she isn’t here,” the attending doctor told him. “She was discharged last night.”

“Last night? How is that possible?” he asked.

“She wasn’t in labor at all; she just had a full bladder. It’s a case of pseudocyesis,” the doctor replied, leaving a chastened Dr. Radebaugh to look up the diagnosis.

Despite Dr. Radebaugh’s embarrassment, his unfamiliarity with the woman’s condition was hardly surprising. Pseudocyesis, or false pregnancy, is rare, occurring at a rate of 1 to 6 for every 22,000 births. Though scientists are still largely baffled about what causes it in humans, recent case studies and studies of similar conditions in animals are beginning to provide insight, exploring the role of hormones and psychology.

Those who suffer from the disorder present a constellation of symptoms that mystify even seasoned practitioners. Not only do they fervently believe they are pregnant, but they also have bona fide symptoms to back up their claims, like cessation of menstruation, abdominal enlargement, nausea and vomiting, breast enlargement and food cravings.

A few patients with pseudocyesis even test positive on pregnancy tests, said Dr. Paul Paulman, a family practitioner at the University of Nebraska Medical Center.

“Every sign and symptom of pregnancy has been recorded in these patients except for three: You don’t hear heart tones from the fetus, you don’t see the fetus on ultrasound, and you don’t get a delivery,” Dr. Paulman said.

Though the disorder is unusual, cases of false pregnancy have been reported in human societies since ancient times, providing evidence that the phenomenon is not bound by time or culture. In 300 B.C., Hippocrates described 12 women who “believed they were pregnant,” and Mary Tudor, the English queen, is widely believed to have suffered from pseudocyesis. (Some commentators say the violent acts that gave her the nickname Bloody Mary were reactions to finding out she was not carrying an heir after all.)

For hundreds of years, pseudocyesis has largely been the domain of psychiatrists, spawning many psychological theories about the origins of the condition. According to Sigmund Freud’s memoirs, his most famous patient, “Anna O,” believed she was pregnant with the child of her previous psychoanalyst, Josef Breuer. Freud attributed this development to what he called transference, or the strong attachment patients form with their psychoanalysts — a concept that would later form the cornerstone of Freudian theory.

Other psychiatrists have suggested that pseudocyesis occurs in patients who desperately want to become pregnant — or who have a strong desire to be involved in a family member’s pregnancy experience. In a recent issue of the journal Psychosomatics, Dr. Biju Basil, a psychiatrist at Drexel University, reported a case of a woman who went through false delivery at the same time her son’s girlfriend was giving birth.

“She started having labor pains. She had been pregnant before, and she said they felt exactly the same,” Dr. Basil said. “She even gave a ‘final push’ the way she had when she delivered her own children.”

Dr. Basil speculated that the woman’s condition arose from a deep-rooted desire to participate more fully in the birth of her first grandchild.

“Since she was not very appreciative of her son’s girlfriend, she was never welcome in their house,” he said. “She wanted to play a more active part in this new life that was coming into the world.”

Still, for all the theories about false pregnancy’s origins in the subconscious, biological studies suggest it may be in part hormonally mediated as well. Because of the small number of people who have the disorder, no large-scale studies have been conducted to establish a typical hormonal profile of pseudocyesis patients. But case studies at the University of Michigan and elsewhere indicate that many patients have elevated levels of hormones like estrogen and prolactin — compounds that can cause physical symptoms like abdominal swelling and milk excretion, as well as psychological ones like wanting to bond with a baby.

This raises the possibility that pseudocyesis is the result of a delicate mind-body feedback loop: an initial emotional state induces abnormal hormone secretion, which in turn has its own physical and psychological effects. According to Dr. Mary Erskine, a biologist at Boston University who studies the neurology of reproductive systems, anxiety may be one emotional state that helps set this feedback loop in motion.

“Stress can really influence the regularity of an ovarian cycle,” Dr. Erskine said.

In dogs — a species with much higher rates of false pregnancy than humans — the disorder has been traced to high levels of certain reproductive hormones, in particular prolactin. Unlike humans, dogs have a long late phase of their ovarian cycle during which an ovarian structure called the corpus luteum produces large amounts of progesterone.

If the dog does not become pregnant, the corpus luteum wears out slowly, over a period of up to 70 days. The consequent drop in progesterone levels causes high levels of prolactin secretion, giving rise to milk production, an enlarged abdomen and a host of misdirected mothering behaviors.

“We get dogs that start guarding their stuffed animals and acting like they’re their babies,” said Dr. Chris Cauble, a veterinarian in Glendale, Calif., who regularly treats dogs with pseudocyesis. “It’s amazing how powerful these hormones are and the emotional effects they can have.”

The quickest way to treat false pregnancy in dogs, he added, is to give them shots of another hormone like testosterone, which quickly brings prolactin levels back into the normal range and stops the associated symptoms.

Because study subjects are in such short supply, Dr. Paulman is not optimistic that human pseudocyesis will ever be completely scientifically understood. Still, he hopes that continued study of individual cases will produce a clearer portrait of how the brain can send the endocrine glands into such a frenzy that a woman who is not pregnant can appear to be in screaming labor.

“The pituitary gland is located right at the base of the brain, and that’s where all the hormones come from” in pregnancy, he said. “This is one of the classic examples in medicine of how the mind affects the rest of the body.”

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