Study criticizes routine use of ob/gyn ultrasound screening

September 16, 1993

Results of a large-scale study released last week imply that ultrasoundis overused in routine screening of pregnant women who are atlow risk of developing complications during pregnancy. The studydropped a media bombshell on an industry already reeling

Results of a large-scale study released last week imply that ultrasoundis overused in routine screening of pregnant women who are atlow risk of developing complications during pregnancy. The studydropped a media bombshell on an industry already reeling froma slowdown in ultrasound scanner purchasing.

The study, known as the Routine Antenatal Diagnostic Imagingwith Ultrasound (RADIUS) project, was published in the New EnglandJournal of Medicine Sept. 16 and figured prominently in news headlinesaround the country.

The study claimed that up to $1 billion could be saved eachyear if ultrasound scans were limited to high-risk pregnant womenand those who develop problems during pregnancy.

"While routine ultrasound is advocated widely by manyin medicine, we found the test is not necessary for normal pregnantwomen," said the study's lead author, Dr. Bernard Ewigmanof the University of Missouri School of Medicine in Columbia,MO. "Our study shows that most normal pregnant women willhave a healthy baby regardless of ultrasound screening."

Researchers in the $6 million study examined 15,000 pregnantwomen over the course of five years. Women were chosen from 109obstetrical and family medicine practices in six states, withhigh-risk women excluded from the study population. Two sonogramswere obtained from 94% of the women in the experimental group;the first between 18 to 20 weeks and the second between 31 and33 weeks of pregnancy. In the control group, 2% of the women receivedscreening exams, at similar intervals.

The rate of adverse outcomes in the experimental group was5%, compared to 4.9% for the control group. Similar numbers ofwomen in each group delivered prematurely, and birth weights didnot vary between groups.

Will the RADIUS study have an impact on scanner purchasing?If so, it couldn't have come at a worse time. Two of the industry'smajor players, Bothell, WA-based ATL and Acuson of Mountain View,CA, have already undergone painful restructuring efforts due toslow scanner sales (SCAN 9/8/93 and 6/16/93). ATL and Acuson scannerswere cited by RADIUS investigators as among the models used inthe study.

Representatives of both companies downplayed the study's potentialeffect on sales, however. In-office ob/gyn practices, which performroutine screening most often, are not a major source of productsales for either company.

ATL spokesperson Jane Hedberg said that about 5% of the vendor'ssales are to ob/gyn offices.

"The ob/gyn office business is a small fraction of ouroverall revenue," Hedberg said. "We don't feel (thestudy) is going to have much of an impact on our sales."

That sentiment was echoed by Dennis Meister, marketing managerfor ob/gyn ultrasound at Acuson. Most of the company's sales arehospital-based machines used primarily when clinically indicatedin high-risk pregnancies, as opposed to routine screening. Thecompany's scanners were used in the study because Acuson machinesare often located in academic institutions of the type that conductstudies like the RADIUS project, Meister said.

Ultrasound manufacturers might even find a silver lining inthe study, in that it proved the utility of clinically indicatedultrasound, according to Dr. Beryl Benacerraf, a clinical professorof ob/gyn and reproductive biology at Harvard Medical School.

While only 2% of the subjects in the control group receivedroutine screening scans, close to half of the control populationreceived clinically indicated scans for complications such asvaginal bleeding, she said.

Routine scanning has never been accepted by the medical community,Benacerraf said. While the study may quiet proponents of routinescanning, it will not lead to a significant reduction in proceduralvolume.

"Things were evolving toward routine screening,"Benacerraf said. "This puts the brakes on that. This willnot change clinical practice."

Benacerraf also questioned the $1 billion figure cited as theamount that could be saved by eliminating routine screening.

"No one reimburses for routine scans," Benacerrafsaid. "The $1 billion is not being spent."