Flying in pregnancy is generally safe, and most women can travel without difficulty. The complications are mainly practical — timing, paperwork and insurance — rather than medical.

When you can fly

The commonly applied limits are:

  • Up to 37 weeks for a single pregnancy
  • Up to 32 weeks if you are carrying twins or more

These reflect the risk of going into labour rather than any danger from flying itself.

Airline rules vary, and they change. Many airlines require a letter from your doctor or midwife confirming your due date and that you are fit to fly, typically from around 28 weeks. Some set earlier limits, and rules can differ between a carrier's own flights and its partners.

Check directly with the airline you are flying with, and do it before you book. Do not rely on what a friend was allowed to do, or on what any website — including this one — says the rules are.

The best time to travel

The second trimester is usually most comfortable: nausea has generally settled, energy is better, and you are not yet close to the airline cut-offs.

Is it safe for the baby?

Yes. There is no evidence that flying increases the risk of miscarriage, early labour or problems with the baby's development. Cabin pressure changes may make you feel bloated or uncomfortable but do not harm your baby. Airport security scanners are safe in pregnancy.

The one real risk: blood clots

Pregnancy increases your tendency to form clots, and long periods of sitting still adds to it. Deep vein thrombosis (DVT) is the one genuine risk of long-haul flying in pregnancy. The overall risk remains low, and it can be reduced considerably:

  • Wear properly fitted compression stockings — the most effective single measure. Get the correct size rather than guessing.
  • Get up and walk around the cabin every hour or so when it is safe to do so.
  • Do seated exercises — flex and circle your ankles regularly.
  • Drink water steadily, and avoid alcohol and excessive caffeine.
  • Book an aisle seat so getting up is easy rather than awkward.

If you have had a clot before, or have other risk factors, speak to your doctor before flying — you may need additional preventive treatment.

Practical preparation

  • Carry your maternity notes in your hand luggage, not in the hold.
  • Get a fit-to-fly letter in good time if you will be past about 28 weeks.
  • Check your travel insurance carefully. Many policies exclude pregnancy-related problems altogether, or beyond a certain number of weeks. This catches people out, and medical care abroad is expensive.
  • Find out what maternity care is available at your destination, in case you need it.
  • Keep medicines in your hand luggage in their original packaging.
  • Wear loose clothing and comfortable shoes; feet swell on flights.

Your destination matters as much as the flight

  • Zika virus — can cause serious birth defects. Pregnant women are advised to avoid areas with active transmission. Check current advice for your destination.
  • Malaria — more severe in pregnancy, and not all preventive medicines are suitable. Get specific advice well in advance.
  • Vaccinations — some are not recommended in pregnancy, and some need to be given well before travel. Do not leave this to the last week.
  • Food and water hygiene — take more care than usual, as illness is harder to manage in pregnancy.

When not to fly

Speak to your doctor before booking if you have a high-risk pregnancy, are expecting twins or more, have had bleeding, have placenta praevia, have had a previous preterm birth, have significant anaemia, or have any serious medical condition. Flying may still be fine — but that should be a considered decision rather than an assumption.

The bottom line

Flying is safe for most pregnant women, with the second trimester the easiest time to travel. Check your specific airline's rules before booking, get a fit-to-fly letter if you will be past 28 weeks, and check what your insurance actually covers. Compression stockings and moving regularly are the main things to get right on the day.

References

  1. National Health Service. Travelling in pregnancy [Internet]. NHS; [cited 2026 Jul 22]. Available from: https://www.nhs.uk/pregnancy/keeping-well/travelling/
  2. Royal College of Obstetricians and Gynaecologists. Patient information leaflets [Internet]. London: RCOG; [cited 2026 Jul 22]. Available from: https://www.rcog.org.uk/for-the-public/browse-our-patient-information/
  3. National Health Service. Keeping well in pregnancy [Internet]. NHS; [cited 2026 Jul 22]. Available from: https://www.nhs.uk/pregnancy/keeping-well/