• Pregnant women should avoid flying after 36 weeks of pregnancy.
  • The best time to fly is during the second trimester because pregnancy symptoms are less severe and there’s a lower risk of an obstetric emergency.
  • For a comfortable, complication-free flight while pregnant, prepare beforehand by staying hydrated, getting up and walking around every 2 hours or so, and bringing a doctor’s note.
  • This article was medically reviewed by Karen Duncan, MD, who is an assistant professor with the Department of Obstetrics and Gynecology at NYU Langone.
  • Visit Insider’s homepage for more stories.

So you’re getting ready for a vacation, or maybe a trip to see family, but you’re also getting ready to have a baby. Travel can be stressful enough without worrying about your health. Here’s what you need to know about flying while pregnant.

It is generally safe to fly while pregnant

Air travel should not have any adverse health effects on your pregnancy, says Julia Simon, an assistant professor and associate program director for the OB-GYN residency at the University of Chicago Hospital.

“I have patients who fly all the time during their pregnancies,” Simon says. “It all just comes down to what makes the patient feel more comfortable.”

As long as you’re having a healthy, normal pregnancy, you can treat flying mostly the same way as everyone else. But the American College of Obstetricians and Gynecologists (ACOG) does not recommend air travel for pregnant women who have medical or obstetric conditions, like preeclampsia, that could require emergency care.

So if you're experiencing any complications during pregnancy, doctors say it's better not to risk it. The same goes if you're planning to travel to high altitudes while pregnant.

The 2nd trimester is considered the best time to fly

Simon says the second trimester may be the best time to fly, since that's when you'll likely be over your nausea and will have more energy.

In addition to nausea, fatigue and increased urination will likely make for an unpleasant airplane trip during your first trimester. And your growing belly during your third trimester might make the trip downright uncomfortable, especially since you'll be wearing a seatbelt.

Moreover, the ACOG says it is most common for obstetric emergencies to occur during the first and third trimesters.

You probably shouldn't fly after 36 weeks of pregnancy

Most doctors recommend that expecting mothers don't fly or take long trips (even by car or train) after they reach 36 weeks in their pregnancy.

In addition, many airlines have restrictions on flying later in pregnancy, and you should check the airline's policy before you travel. Requirements are more stringent for international flights, and you'll usually need a doctor's note to travel.

If you have a more complex pregnancy - such as if you're older than 35 or have had previous complications - doctors might recommend that you stay home earlier than 36 weeks. The reasoning has more to do with your birth plan than with any dangers involved in the travel itself.

"There's no physical concerns for a baby's health, and with a doctor's approval you can even fly after that point," Simon says. "We just want you to limit travel so you can have access to your physicians, should you go into labor."

How to prepare for flying while pregnant

Simon recommends pregnant women think about a few key factors before they travel, to stay comfortable and avoid medical complications.

No matter when in your pregnancy you travel:

  • Get up and walk around every couple of hours. It's important for everyone to keep their blood circulating to avoid deep-vein thrombosis (DVT) and blood clots, but especially for pregnant women who can suffer from leg and foot swelling. That's why doctors will sometimes recommend you grab an aisle seat to make it easier to get up and walk around during the flight.
  • Stay hydrated. Good hydration is key for pregnant women, and you shouldn't cut back on fluids just because you don't want to bother with an airplane bathroom. Here's some more information on how to stay hydrated, because you may need more than just 8 glasses of water a day.
  • Bring a doctor's note. If you're concerned, or if you're traveling with a doctor's permission late in your pregnancy, you should bring a doctor's note to head off any questions at the gate. It can be as simple as a letter on the doctor's office letterhead with your doctor's notation on your due date and how far along you'll be while traveling.

Simon reminds patients that if they're planning a trip like a babymoon or other vacations, to check in with their doctor and the CDC to make sure they're up to date on vaccinations they might need or necessary travel precautions (like against the Zika virus, which can affect a fetus at conception).

Ultimately, flying while pregnant may not be so different from traveling regularly. Just be sure to take good care of yourself. That means monitoring your comfort, having a plan for emergencies, and practicing good hygiene to avoid infections and illness.

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