You would require a doctor’s approval and letter to allow you to fly if your pregnancy is in the 3rd trimester – 29 weeks +. After 35 weeks, there is a ‘no fly rule’ even if you did manage to obtain a doctors note.
The airlines have every right to be cautious as they do not want you to go into labour an hour after take off! Landing a plane will cost the airline a lot of money, as well as severely disrupt and delay the other passengers. and if for some reason – they could not land the plane, they don’t want to be held entirely responsible for the health and wellbeing of you and your baby if you give birth in mid flight.
All airlines require a woman to present a medical consent form from her doctor after the 29th week of pregnancy and you may also need to fill in a form if you plan to travel this later than this in the pregnancy, stating that you are aware of the risks involved and that you won’t hold the airline liable for any complications that might arise (early/unexpected labour, complications during birth, complications with the baby that may result in injury or death after birth, DVT or clotting in the placenta that may result in injury or death to both you or the baby) due to the nature of the method of travel and the risks involved.
It is unlikely that you would be able to obtain medical insurance be able to get travel insurance after 29 weeks because you would be considered too high a risk to invest in. The other issue is – is that you also may not be able to have certain vaccinations necessary for your trip, so unless you have traveled to that destination previously, and have had boosters in the past 5 years, then you are at risk of picking up a bug that might cause serious health complications for you and your baby.
As a rule of thumb – the 2nd trimester (14-28 weeks) is a more suitable time to fly, as most women feel more comfortable, (passed morning sickness) and the risks of miscarriage and premature labor are lowered considerably.