I know air travel is out late in pregnancy, but I'm in my first trimester and fly occasionally for business. Do I need to stop now?
Probably not. One concern with air travel is exposure to solar radiation, as excessive amounts of any type of radiation may put a fetus at increased risk for childhood cancers. However, the American College of Obstetricians and Gynecologists states that such risks from "casual" air travel under normal solar conditions are negligible.
The National Council on Radiation Protection and Measurements recommends that a pregnant woman receive no more than 1 millisievert of radiation exposure during a 40-week pregnancy. One round-trip, cross-country flight delivers 6 percent of that exposure, while a round-trip New York-Tokyo flight constitutes 15 percent. Occasional travel is therefore within the safe range of exposure. The Federal Aviation Administration also restricts radiation exposure during abnormal solar conditions by redirecting flights to safer altitudes.
That said, pregnant women who travel frequently or work as pilots or flight attendants may need to modify their schedules. For a per-trip radiation calculator, visit http://jag.cami.jccbi.gov/cariprofile.asp.