A few days ago, some friends in the mother\’s group raised this question: Why do some people vomit to the point of doubting their life when they are pregnant, while some people have no morning sickness at all? I started vomiting food and water when I was pregnant, and I felt like vomiting when I smelled food. Every time I cook upstairs or downstairs, I have to put on a mask quickly. By the time I was four months pregnant, I was vomiting almost twenty or thirty times a day…