This information is intended for pregnant women who are thinking of travelling by air. The information is relevant for short haul (<4 hours) and medium / long haul (≥4hours) flights.
Will flying harm the mother or the baby?
Like all other passengers, pregnant women on a flight experience changes in air pressure and decrease in humidity. If the pregnancy is straightforward and the mother is healthy, there is no evidence that these effects are harmful for the mother or the baby. There is also no evidence that flying will cause miscarriage, early labour or the waters to break. Passengers on a flight are also exposed to a slight increase in radiation, but occasional flights are not considered to present a risk to the mother or the baby.
When is the safest time to fly during pregnancy?
After 12 weeks. Some pregnancy complications may happen during the first trimester, such as miscarriage and ectopic pregnancy. It is safer to fly when the pregnancy is considered more stable after 12 weeks. Women also tend to have pregnancy sickness during the first trimester. Flying during this period may make the morning sickness worse.
Uncomplicated single pregnancy: before 37 weeks; uncomplicated twin pregnancy or single pregnancy with risk factors for preterm delivery: before 32 weeks. Women in advanced pregnancy may go into labour at any time. Therefore, most airlines do not allow pregnant women to fly after a certain gestational week. Pregnant women who intend to fly must check with the airline for their policy.
Risk of flying – Deep vein thrombosis (DVT)
A deep vein thrombosis (DVT) is a blood clot that forms in the veins of the leg or the pelvis. If the blood clot travels to the lungs and causes pulmonary embolism (PE), the condition can be life threatening. Women who are pregnant and for up to six weeks after the birth have a higher risk of developing a DVT compared with women who are not pregnant.
There is an increased risk of developing DVT while flying, due to sitting for a prolonged length of time. The risk of having DVT increases with the length of the flight. Therefore, passengers on medium or long haul flights have increased risks of DVT. Other risk factors for DVT include a previous history of DVT and overweight. The more risk factors a woman has, the higher the risk for her to have DVT.
How to reduce the risk of a DVT?
To minimise the risk of DVT on a medium or a long haul flight, the following measures can be done:
1) Wear loose-fitting clothing and comfortable shoes;
2) Take regular walks around the plane during the flight;
3) Do in-seat exercises every 30 minutes or so, the airline should provide information on these;
4) Have glasses of water at regular intervals throughout the flight, avoid drinks that contain alcohol or caffeine;
5) Wear graduated elastic compression stockings, these stockings are different from standard flight socks and can be bought from pharmacies.
Pregnant women who are considered as having a high risk of DVT may be advised to take heparin injections. Heparin is a blood thinner and helps prevent DVT. A heparin injection should be taken on the day of the flight and daily for a few days afterwards. Low-dose aspirin does not appear to reduce the risk of DVT.
Making a decision to fly
If you are thinking about flying, the following questions may help you decide whether or not to fly:
Why do you want to fly at this particular time?
Is your flight necessary?
How long is your flight? Will this increase your risk of medical problems?
How many weeks pregnant will you be when you travel and when you return?
Your chance of going into labour is higher the further you are in pregnancy.
It is also important to remember that having a miscarriage, whether you fly or not, is common (one in five) in the first three months of pregnancy.
What are the medical facilities at your destination in the event of an unexpected complication with your pregnancy?
Have you had all the relevant immunisations and/or medication for the country you are travelling to? Have you checked with your doctor how these affect your pregnancy?
Does your travel insurance cover pregnancy and/or care for your newborn baby if you give birth unexpectedly? There is huge variation among travel insurance policies, so it is worth checking before you decide to fly.
Have you discussed your travel plans with your doctor and informed your doctor that you are thinking about taking a medium or long haul flight?
What should a pregnant woman take when flying?
Her hand-held pregnancy notes, if any. Any medication she is taking. If she is over 28 weeks pregnant, the airline may ask her to get a letter from her doctor stating when her baby is due, confirming that she is in good health and is not at any increased risk of complications. Some airlines have their own forms or documents. Pregnant women who intend to fly must check with the airline. Travel insurance documents.
Does a pregnant woman have to go through a security scanner?
A pregnant woman has to go through the normal security checks before flying. Going through the security scanner is not considered to be a risk to the mother or the baby.
Can a pregnant woman wear a seatbelt?
A pregnant woman must wear a seatbelt. She should ensure the strap of the seatbelt is reasonably tightly fastened across the top of her thighs and then under her bump. She can ask the cabin crew for a seatbelt extension if necessary.
What happens if a pregnant woman goes into labour on the flight?
Any pregnant woman has a small chance of going into labour early or for her waters to break early. If this happens on a flight, there is no guarantee that other passengers or crew members are trained and experienced to help her give birth safely. As a result, the pilot may have to divert the flight to get help.
