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Pregnancy and Flying

Pregnancy

Can I continue flying (domestic as well as international flights) while I am pregnant?
When a pregnant passenger is flying on a commercial airline she should not be concerned about the effect of flying on the developing fetus. 
I have read some things telling me that flying while pregnant is okay and some other things that say I should worry about an increased risk of cancer for my children if I do fly while I'm pregnant. Can you clarify this?
First, let me mention that the background risks for birth defects are 3% and for miscarriage are 15%; this is the normal incidence. The most important factor with regard to radiation risks is the dose. Fortunately, when you are flying in a jet at 30,000 feet altitude the exposure is extremely small and for only a short period. Based on our knowledge of the amount of radiation to result in birth defects or miscarriage, there is no risk from commercial flying. The reason why consultants differ in their statements on the risk of childhood cancer is that there is a theoretical risk for cancer from any exposure of radiation (ionizing). But when the dose is as low as it is when you are flying, the theoretical risk is dwarfed by the spontaneous risk of cancer. So you could say the cancer risk from flying is very, very, very, very small or you could say it should be of no concern because the dose is so low.
Is it okay to fly on small planes while pregnant?
If you are concerned about radiation exposure, then your exposure would be lower when flying in a small plane, because it will fly at a lower altitude. The radiation exposure in both the small and the larger planes is too low to increase your risk for birth defects or miscarriage.
Should I wear a lead apron while I am pregnant and flying in an airplane?
Using a lead apron while flying is unnecessary because (1) there is very little extra radiation exposure as a result of flying and (2) some types of radiation that may cause exposure while in-flight would not be stopped by a lead apron.
Are there any weeks of pregnancy that are safer than the others when flying on a commercial airplane?
The exposure to radiation during a commercial flight is very low and is below the dose that could potentially harm the embryo or fetus at all stages of gestation. Therefore, when you fly stage of gestation is irrelevant from a radiation standpoint.
Quite a few of my flight attendant colleagues have had miscarriages, some more than once. Is there a connection with the job, the exposure to radiation, pressurized cabin, low oxygen levels?
Spontaneous abortions are a very common problem regardless of occupation. In the first month of pregnancy about half of the fertilized eggs do not survive, most because of lethal chromosome abnormalities. Once a woman misses her period and knows she is pregnant, 15% of the embryos miscarry. There are about 24 known medical problems that are responsible for pregnancy losses. Smoking and drinking increase the risk, as does thyroid disease and diabetes. The radiation exposures in flight are too low to contribute to the risk of abortion and the oxygen levels in a pressurized cabin are more than adequate for the mother and fetus. Stress may be a factor, but it will vary with the individual. Studies have been performed in female flight attendants, but the number who are pregnant and continue to work is small, and they have not indicated an increase in spontaneous abortions.
I am a few weeks pregnant and have taken two transcontinental flights and will be taking two more soon. Is this too much radiation exposure?
While it is true that your exposure to background radiation increases at higher altitudes, the exposure that you have and will receive will not increase your risks for birth defects or miscarriage.
I am planning a round-trip flight from Washington, DC, to Chicago. I have a particular concern about my exposure to radiation because there are solar flares predicted for that week and I will be in my 9th week of pregnancy during my flights. What are the additional risks of radiation we might be exposed to if our flights occur during solar flares and the implications that it could have on my developing baby?
The radiation exposures while flying are not considered high exposures. During your pregnancy you and your fetus will receive about 300 millirad of background radiation, which of course none of us can avoid. In a 10-hour flight you would receive less than 1 millirad. During solar flare periods the exposure may be increased. Some measurements have estimated exposures of 100 times the usual exposure while flying which would bring your exposure in the range of a low-level exposure from many diagnostic radiological procedures. Even this exposure would not increase your risk for birth defects or miscarriage, which is 3% for birth defects and 15% for miscarriage for all healthy women when they begin their pregnancy.
Many questions refer to commercial flights—what about flying in a Learjet that flies at higher altitudes?
Radiation exposure during the Learjet ride will not increase your risk of miscarriage. According to a recent paper (Bottollier-Depois J F, Chau Q, Bouisset P, Kerlau G, Plawinski L, Lebaron-Jacobs L. Assessing exposure to cosmic radiation during long-haul flights. Radiat Res. 153(5 Pt. 1): 526-32; 2000), the radiation exposure received by passengers during a Concorde flight is about 1 millirem (mrem—a unit of radiation dose) per hour. This is a good reference since the Concorde flies at approximately 55,000 feet and a Learjet may be between 40,000 and 50,000 feet. Put in perspective, that is about one day of normal background radiation (radiation exposure we receive every day from naturally occurring radiation sources). The dose that is allowed by the Nuclear Regulatory Commission for a pregnant woman who is occupationally exposed to radiation is 500 mrem.
Effect on Conception

I fly quite a bit because of my work. My hu*****and and I are trying to conceive and I wonder whether my flying will affect my chances.
There is no reason for concern regarding a possible effect on fertility of radiation from a few airplane flights. Because there is a threshold dose for radiation effects on fertility, when we are below the threshold, the risk becomes clinically insignificant. It would take several hundred thousand commercial flights to reach the threshold dose. That would be about two flights per day for about 700 years.
What is the effect of radiation during commercial flights on sperm and the ability to conceive?
The amount of radiation exposure received during commercial flights is too low to affect sperm.
I am a flight crewmember and consistently nursed my child even after long flights. Is it or has it been safe for me to nurse?
There are no known adverse effects or risks of such low doses of radiation (like those you received while flying) on nursing a baby.
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