Pregnant women are not recommended to travel by air after less than 12 weeks and more than 32 weeks of pregnancy. 1. Before 12 weeks of pregnancy: belonging to the early stage of pregnancy, due to the high speed and instability of the initial development of the embryo leads to the possibility of various accidents of pregnant women in the early stages of pregnancy is relatively large. The force of the airplane during takeoff and weightlessness during landing may affect the unstable embryo and aggravate the early pregnancy reaction. 2. 32 weeks pregnant: 32 weeks pregnant women’s abdominal expansion is more obvious, as the uterus increases, the aircraft takeoff, landing, bumps, etc. have induced uterine contractions leading to premature labor, placental abruption and other possibilities. In addition, if a pregnant woman sits on the airplane for a long time without activity, it is easy to cause lower limb thrombosis and other risks. Therefore, it is recommended that pregnant women who are less than 12 weeks pregnant and more than 32 weeks pregnant should change to a more convenient and comfortable mode of transportation. If you have any other questions, it is recommended to consult a professional doctor for guidance.