Pregnancy Bliss | Reproductive Health Answers
Flying while Pregnant
Many pregnant women find themselves needing to fly. This may be an emergency, on business or even grabbing that short holiday before the new arrival which is bound to change the family dynamic forever. Then there are those women who earn their livelihood through regular flying. These would include commercial pilots and cabin crew.
The overriding issue for the woman is the safety of both herself and her unborn baby. Flying involves exposure to some degree of radiation coming from space and the sun. This is because planes fly where the atmosphere is thin therefore reducing the shielding protection that we get on the ground. It follows therefore that the higher the plane flies and the longer the person flies, the more she is exposed to the cosmic radiation.
There is minuscule radiation on the ground and it goes down the nearer you are to the sea-level. When flying and the jet is cruising at 33,000 feet (10,000 metres), the level of radiation exposure is 35 times that at sea-level. It is 64 times when the jet reaches 39,000 feet (13,000 metre), cruising altitudes seen in transcontinental flights. This might look alarming but in fact, for an occasional flier, this level of exposure is still perfectly safe.
The question mark therefore is only on the regular long-haul air crew. In theory, the very early part of pregnancy when the fetus is at its most vulnerable would be the risky period. With many young women working in the industry and many actually flying during that time before some are even aware of their pregnancy, it is somewhat reassuring that there is no real scientific evidence that their babies are adversely affected. Nonetheless, in Europe though not in the United States, air crew are classified as radiation workers and their exposure levels are monitored.
Pregnancy is a thrombogenic condition. What this means is that, when pregnant, a woman’s risk of developing thrombosis is increased. That is an established fact. What is more questionable is the extent of risk of thrombosis posed by flying. The evidence is simply thin on the ground.
In theory, flying, especially long-haul, may be a risk factor for deep vein thrombosis (DVT) because of the associated enforced prolonged sitting down. This in some cases might be associated with reduced fluid intake leading to dehydration which is an independent risk factor for DVT. Some experts therefore argue that a flier would negate any perceived increased risk of thrombosis associated with flying by avoiding those two issues. This is why it is advocated for all passengers (not only the pregnant) to make regular stretching exercises and walk about in the cabin and ensure regular fluid intake. For pregnant women, pressure stockings may also aid circulation in the lower limbs.
What role Aspirin?
Low-dose Aspirin for a flier is controversial. Aspirin is an anti-platelet agent which is of proven value in preventing arterial thrombosis (such as for people with or at risk of angina). Deep vein thrombosis occurs through an entirely different mechanism and therefore Aspirin is unlikely to be of any value in preventing this. It is, nonetheless, still advised by a number of bodies for people planning to fly.
Airlines have different rules regarding the upper limit beyond which they would not allow a pregnant woman to fly. As a general guide, almost all airlines decline to fly women beyond 36 weeks of gestation and for some it is 34 weeks. In the phase between 28 and 36 weeks, most airlines will demand that the passenger bring her doctor’s letter stating that she is fit to fly and that she is unlikely to go into labour within 36 hours.
Beyond the rules, a pregnant woman can do a few things to facilitate smooth travel. If unsure about the airlines regulations, it is worthwhile to contact customer services to ensure there will not be any last minute hiccups at the boarding gate. That call can also be used to request a bulkhead seat with more legroom. Of-course if she can afford it, a pregnant woman can book a first/business class seat as these tend to have a flat bed option.
If a woman is carrying twins or any other form of multiple pregnancy, she needs to be more cautious since her risk of going into labour early is significantly higher and of-course any labour in the skies with twins is likely to pose a much more formidable challenge. The cut-off points for flying should therefore be a lot lower.
Last update: March 18, 2013