As long as your pregnancy is normal, you can travel by plane and continue with your travel plans. It is said that the best time to travel is week 14 to 27. During this time, the chance for miscarriage is low and no more morning sickness so you can take advantage of sleeping late and enjoy your vacation.
You can still fly even if you are on your 36th week of pregnancy but some airlines do not allow pregnant women of 28 weeks or so to travel because they are worried that you might give birth in the plane. Check airline policy first before booking a trip and get a written permission from your doctor that you are safe to travel and won’t into labor during the travel period. Also have yourself checked by your doctor before travelling to ensure that you are in good condition.
Your bags and luggage are the only ones who will be x-rayed. Travelers will pass through a metal detector upon entering security gate at the airport.
The risk of miscarriage and abnormalities in the unborn baby when exposed to atmospheric radiation is low if travelling few times a year.