Pregnant women, who in the past were confined at home or were expected to lead a sedentary existence, are more active today and travel for both business and pleasure. Air travel, which is a convenient mode of transport for such purposes, can be undertaken until the end of the 35th week. This stipulation varies slightly with different airlines, which are also likely to require a medical certificate that specifies the expected date of delivery. As a precautionary measure it is advised to check with the immigration regulations of the country to be visited, as some refuse entry to passengers in the advanced stages of pregnancy.

Background cosmic radiation levels are higher at altitude. Air travel should, therefore, be avoided, if possible, during the first three months of pregnancy as small amounts of radiation can be harmful to the foetus.

On board expectant mothers (as well as other passengers) should take into consideration the various aspects of the cabin environment. The following specific points should be noted.

Wear flight socks during air travel (see shop)
In general, your water intake should be maintained and foods that produce intestinal gas should be avoided prior to a flight or on board. The resultant expansion of gases in the intestines can cause discomfort.
As pregnancy tends to increase the blood's viscosity, expectant mothers should try to be more active than usual on board. They should also request and isle seat and spend up to 15 minutes each hour walking about.
Seat belts should be worn low around the pelvis.
Methods used to avoid jetlag should exclude drugs, focusing instead on sleep patterns and airline schedules.
If there is an opportune time to fly First or Business Class, it is during pregnancy. Not only does the use of leg rests encourage better circulation, but less cramped and crowded conditions result in reduced fatigue and greater comfort.

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