For most people with a straightforward pregnancy, air travel is considered safe, particularly in the middle of pregnancy when nausea has often settled and the risk of early complications has passed. Many airlines restrict travel in the final weeks and may require a letter from your doctor or midwife confirming your due date, so check the airline's policy in advance.
Long flights slightly raise the risk of blood clots, so move around, do leg exercises, stay hydrated, and ask whether compression stockings are advisable. Wear your seatbelt low under the bump.
Flying may not be recommended if you have certain complications such as severe anaemia, a high risk of preterm labour, or significant placental issues. Discuss your plans with your provider, and make sure you have appropriate travel insurance and know where you can get care at your destination.