Radiation Scans in Pregnancy Rising

Pregnant women are being exposed to more than
twice the amount of radiation from medical imaging scans than they were a
decade ago, potentially placing themselves and their unborn babies at risk of
future health woes, researchers report.

Although the average amount of radiation a woman received during any scan
was well below the accepted limits for exposure in pregnancy , it's hard to know what the health effects will
be decades down the road, says Philip O. Alderson, MD, chairman of radiation
oncology at Columbia University in New York.

Exposure to radiation in pregnancy has been shown to place both the mom and
her baby at increased risk of cancer ; the child may also face
learning and developmental problems. The health risks are cumulative; the
greater one's exposures throughout a lifetime, the greater the risk.

Alderson, who was not involved with the work, moderated a news conference to
discuss the findings at the annual meeting of the Radiological Society of North
America.

Rise in CT Scans Drives Trend

For the study, Brown University researchers reviewed 5,235 radiological
examinations -- X-rays, nuclear medicine scans, and computed tomography (CT)
scans -- performed on 3,249 pregnant women from 1997 to 2006.

Over the 10-year course of the study, the number of women imaged increased
91% and the number of actual examinations performed on pregnant women shot up
125%.

A dramatic 25% rise in CT scans, which deliver more radiation and therefore
pose more health risks than other procedures, drove the troubling trend, says
Elizabeth Lazarus, MD, assistant professor of diagnostic imaging at the Brown's
Warren Alpert School of Medicine.

The use of nuclear medicine scans increased 17% over the 10 years of the
study; X-rays rose just 7%.

Ask About Non-Radiation Options

Nearly one-third of the CT scans were of the abdomen or pelvis, "where
the fetus is directly in the beam of radiation," Lazarus says.

She tells WebMD that pregnant women who are scheduled for a radiological
exam should ask their doctors about alternative tests that do not involve
radiation. They may also want to inquire about the danger of putting the test
off until after the pregnancy, she adds.

Lazarus says that suspected appendicitis was the most common reason that the pregnant
women got an abdominal CT.

Magnetic
resonance imaging (MRI) scans can also diagnose appendicitis and do not
emit radiation, Lazarus says. However, they are not available at every
hospital.

The researchers stress that in many cases, CT scans are appropriate in
pregnancy.

"CT scans are making a terrific contribution to the health of our
population," Alderson says. "The problem is overutilization."

Why So Many Scans?

So why are pregnant women undergoing so many more scans than in the past?
According to Lazarus, some of this increase is due to the development of new
imaging techniques that better diagnose health problems.

But doctors, hospitals, and insurers seeking to make accurate yet fast
diagnoses are also playing a role, she says. Many practice "defensive
medicine in an increasingly litigious environment" in which health care
providers fear malpractice suits if they miss a diagnosis, she says.

By Charlene Laino
Reviewed by Louise Chang
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