The safest time to fly during pregnancy is before 37 weeks or, if carrying twins, before 32 weeks, new advice says.
The Royal College of Obstetricians and Gynaecologists says flying is not harmful during a low-risk pregnancy, but there may be side-effects.
If more than 28 weeks pregnant, a woman should take her medical notes and a GP’s letter.
Many airlines have their own rules on when pregnant women can fly.
Although everyone who flies is exposed to a slight increase in radiation, there is no evidence that flying causes miscarriage, early labour or a woman’s waters to break.
You can find more information about this on the BBC News Health page here
