Before I found I got pregnancy, I also bought air ticket and hotel voucher to go South Korea for shopping. As I had morning sickness and was very tired everyday during that period, I did cancel the package by myself. It really depends on your health situation. If you can cancel it, i suggest you should cancel, because the first 3-mth is quite critical and you would not enjoy the trip. However, you can plan to have trip during the 4th-6th month, as you will have full of energy during that period.