Exposure to high levels of electromagnetic fields (EMFs) - especially early in pregnancy - can significantly increase a woman''s risk of miscarriage, according to a new study.

Investigators at Kaiser Permanente''s Division of Research in Oakland, Calif., found that exposure to more than 16mG (milligauss) of electromagnetic energy increased a woman''s risk of miscarriage by six times in the first 10 weeks of pregnancy.

"This is a statistically significant finding," says lead author De-Kun Li, MD, Ph.D. "Particularly since previous studies did not measure EMF exposure levels before miscarriage occurred or measure peak exposure during a woman''s typical day."

The results of the study can be found in the latest issue of the journal Epidemiology, published this week.

Researchers asked participants to wear exposure meters to measure peak exposure levels during a single day. What they found was that women who were exposed to high levels of EMFs were more likely to miscarry than women whose daily exposure was lower. The risk of miscarriage was noticeably higher in women with histories of miscarriage or trouble getting pregnant.

Where is a woman likely to be exposed to high levels of EMFs? "Standing right next to a microwave while heating up a cup of coffee in the morning can expose a person to 100 to 300 mG," says Li. He notes that distance from the source of exposure can dramatically reduce the EMF level. For instance, putting a cup of coffee in the microwave then walking away from it can make any exposure insignificant.

Other sources of exposure to magnetic fields can include work equipment such as copiers and fax machines, as well as items found in homes such as electric blankets, vacuum cleaners or hair dryers.

"There are ways to reduce risk and still do the things you''d normally do," says Li. For example, move away from equipment such as copiers while they''re operating; don''t hover over them.

"What we''re saying is, while the findings still need to be replicated in future studies, as a result of this study, it would be prudent for women who are in their first trimester, or know they are at risk of losing a pregnancy, to lower their exposure whenever possible, concluded Li.

The journal Epidemiology is available through its Web site at www.epidem.com.

by Sandy Smith (ssmith@penton.com)