Female Speaker: For more than 10 years Kathryn Daniel worked as a flight attendant. Now she is taking a break from that career to spend time at home in Dover, New Hampshire with her baby son Jared. Kathryn was closely monitored during her pregnancy. She wanted to make sure the physical demands of being a flight attendant wouldn't harm her baby. Kathryn Daniel: I didn't want to work during my last trimester, just because, you get so much bigger. It's very tight on these airplanes and you hit things anyway. I can't walk down the aisles without my hips hitting people and think what my belly is going to do? So I think, I thought more of that kind of convenience so fitting on the airplane more than anything else. Female Speaker: For most pregnant women flying is almost always safe. Women who are in the later stages of pregnancy should check with their airline carrier about travel rules. Most airlines allow pregnant women to fly until about 36 weeks of pregnancy. Airline industry policy requires flight attendants to have a physician sign off on their health status during pregnancy. Kathryn's OB-GYN Mark Chag is with Harbor Women's Health in Portsmouth, New Hampshire. Dr. Mark Chag: Generally the 20 to 26 week range at that point there is a form that you fill out or a letter that you advise that they stop work and they are allowed to do that for the duration of the pregnancy. I've never seen an airline require or even ask a woman to work in the third trimester at all. I think they're aware of the physical, it's a physical job and they don't require women to do that. Female Speaker: But it's not just the physical demands of the job. Airline travel exposes everyone to cosmic radiation, but it's more intense on the crew because of the exposure over multiple flights. So for a pregnant flight attendant, the risk to her and her baby's health needs to be discussed with her doctor. Dr. Kathryn Daniel: I might have known kind of intellectually that it existed, but as far knowing any breadth of information about it, no. And I think that flight attendants on a whole do tend to put any fears if they have, because there are so many now days, somewhere else somewhere that they don't have to really think about it. Female Speaker: Rob Barish is a Ph. D at the Lenox Hill Heart and Vascular Institute in New York City. Doctor Barish says the level of radiation increases with the altitude of the plane. Rob Barish: At approximately 35 thousand feet or so, you're getting the equivalent of about one chest x-ray every three hours on an airplane. In Europe if you're a flight attendant then declare yourself to be pregnant they take you out of the air. Because that one millisievert limit which represents the non-occupational dose and therefore the dose that a fetus can get can be easily reached in a very short amount of flying time. And so, in order to protect the pregnant flight attendant the European carriers basically ground them but continue to pay them. Female Speaker: In 2000, European air carriers adopted this policy in an effort to protect pregnant crewmembers. Patricia Friend, the president of the flight attendants union here in the U.S., believes the policy should be proof that cosmic radiation is an issue to be taken seriously. Patricia Friend: The guidelines are similar, but the problem is there isn't a definitive policy in this country to both inform flight attendants of the potential health risks and or to give them the option that our European sisters and brothers have which is to adjust their schedule if necessary in order to minimize those health risks. That does not exist in this country. Female Speaker: Dinkar Mokadam is an occupational safety and health specialist with the flight attendants union. He has headed up the effort to educate flight attendants about cosmic radiation with the latest publications on its website. Dinkar Mokadam: Exposure is always cumulative. So the more time you spend in the air, the more doses you are going to get.