In the case of pregnant women with normal menstrual cycles, the reaction usually appears around six weeks after menopause, with at least anorexia, anorexia, nausea or desire to vomit, which usually starts at 7-8 weeks. If the pregnant woman has a longer menstrual cycle, not 30 days, but 35 or 40 days, the reaction of nausea and desire to vomit will be delayed later. A normal person may have oil aversion on day 40, start to want to vomit on day 45, and have early pregnancy reactions such as nausea and want to vomit on day 50. In pregnant women with abnormal menstrual cycle, especially those with long menstrual cycle, the early pregnancy reaction will be delayed to 45 days, but it may be 55 or 60 days.