During pregnancy you should take extra care while travelling whether it is your daily commute or a walk in the park or long distance. Travel stress can make your fatigued and the fetus stressed. Long distance travel could also be fatal if it goes awry. Most doctors will advise you to not travel long distance during the first trimester or the first 12 weeks of your pregnancy. However once you cross your first trimester and have plans to travel long distance the best time to do so is your second trimester from the fourth to the seventh month of pregnancy.