1. Feeling Of Nausea. Nausea, also called as morning sickness, is the classic sign of pregnancy, which occurs due to an exceptional rise in the hormonal levels in a woman’s body. Usually, nausea starts when you are about six weeks pregnant (during the first trimester). It is definitely uncomfortable to deal with, but it is generally perceived as a sign of healthy pregnancy. There is not much that can be done about nausea. However, an upset stomach can be settled by eating bland foods.