Study Finds No VDT-Miscarriage Link
The University of Michigan has released preliminary findings in a study of a possible link between video display terminal use and miscarriages.
The study, funded by the March of Dimes, is one of the first major attempts to establish scientifically whether women who work on computers have an increased risk of miscarriage or birth defects in their infants. It was undertaken after reports from across the United States, Canada and Europe of “clusters” of reproductive problems among women who use VDTs.
The preliminary results of the survey, which involved 5,739 state clerical workers in Michigan who participated with the cooperation of their unions and management, were that pregnant women who work less than 20 hours a week at terminals do not appear to be at higher risk of miscarriage than other women.
“Pregnant women who worked one to 20 hours a week at VDTs had the same miscarriage rates as women who did not work at the machines,” said William J. Butler, a professor in the university’s School of Public Health. Butler, an occupational health physician, and colleague Kelley Ann Brix, also of the School of Public Health, announced their findings at the annual meeting of the American Public Health Assn. in Las Vegas.
They also found a “statistically insignificant risk” of increase in miscarriages among women who worked more than 20 hours a week at VDTs. While the scientists thought that their findings indicate it is unlikely that VDTs have a large effect on the outcome of pregnancy, Butler cautioned that the sample was not large enough to rule out the possibility that working more than 20 hours a week at terminals might increase the risk of miscarriage by as much as 5%.
9 to 5 National Assn. of Working Women and the Service Employees International Union quickly responded to the study’s findings. The association and union represent thousands of office workers and have conducted a longtime joint campaign for VDT safety. John Sweeney, president of the union, and Karen Nussbaum, director of 9 to 5, issued a printed announcement saying, “We are concerned . . . that the findings have been used out of context and that working women who need answers--the growing number of VDT operators whom we represent whose jobs require them to sit in front of a VDT most of the workday--may mistake these findings for real answers.”
They also criticized the sample size, charging that the study was limited in its ability to find any but large increases in adverse pregnancy outcomes among VDT users and that it did not include a sufficiently large number of frequent VDT users.
The study’s scientists had themselves announced their results with the admonition that their findings cannot be called conclusive and that further study is needed on pregnant women who use VDTs more than 20 hours a week. They will also continue the research, and are examining the incidence of birth defects and low birth weight among the infants of mothers who work at terminals.
Other research is forthcoming. The National Institute for Occupational Safety and Health has announced that it will do a study of VDT use and pregnancy outcome using a sample of 4,000 workers.
9 to 5 and the union called for more research on related issues such as the effects of stress and musculoskeletal problems on pregnant VDT workers. Brix and Butler said that stress has been suggested as a possible factor in offices where a high rate of miscarriage has been reported, but that there have been too few cases to form conclusions. Along with further research on birth defects, they plan to study the effects of job stress on pregnancy.
