Your wife will be in the mid-trimester when she travels. If everything is normal, like the placental and fetal condition and the maternal condition and if there is no uterine irritability, she can travel, the precaution being to avoid prolonged stay in the same posture and jerky movements. The aim is to avoid excessive pressure on the uterus
. She may use dress and foot wear which are free and comfortable and take sufficient water and electrolytes and try to lie in left lateral position as much as possible. Please get further instructions from your doctor. Good luck.