Early pregnancy travel is fairly uncomplicated and will get your health care provider's green signal if you are not suffering from spotting, hypertension, low blood pressure, diabetes, or if your former deliveries were too premature. If you have not crossed 34 weeks and are past your first trimester, you shouldn't be too worried. But do consult your doctor and talk to the airlines as policies vary from carrier to carrier. These policies change from time to time especially regarding pregnant women and you might have to get a certificate from your doctor...
...stating your which week you are in and certifying that you are in good health.
Travel during early pregnancy is likely to exacerbate morning sickness and hence it would be prudent to keep a couple of air sickness bags handy. Also talk to your doctor about possible anti nausea medications you can take before the flight. Since smoking is banned on flights, it will not trigger off morning sickness, but even strong perfume and sometimes air plane food can cause nausea. Air travel in early pregnancy especially the first trimester may increase the risk of a miscarriage, so avoid the trip if possible or push it to when you cross the period. Most experts suggest that the best time to make the journey is between 18-24 weeks as you are over the danger of miscarriage and morning sickness is likely to have abated.
When you do decide to make the trip, look up various airline carriers and take the one that offers the shortest duration of flying time so you do not spend too much time in air. It is also advisable to fly by major carriers as they contain pressurized air, or in other words, the air in the cabin has a much higher oxygen content than the air outside. Small private airlines are usually not pressurized and it would be prudent to avoid altitudes higher than seven thousand feet. Request the crew for an aisle seat to avoid having to climb over people to go to the bathroom. The best seat possible is the one right behind the wall that divides first and second class passengers as it has more leg room and easier access to the bathrooms.
Experts also point out that pregnancy and air travel can increase the size of the belly if the mother to be has consumed any gas producing food or aerated drinks like sodas or colas. These are best avoided at high altitudes.