How many months into pregnancy will symptoms of morning sickness occur? Pregnancy is a wonderful thing for women, but there are many uncomfortable symptoms during pregnancy, among which morning sickness is a common one. So what causes morning sickness? At what stage of pregnancy does morning sickness occur? Let’s introduce it in detail below. What is morning sickness? Morning sickness refers to the uncomfortable symptoms of nausea, vomiting or retching that occur during pregnancy. Morning sickness is one of the common adverse reactions during pregnancy, and most pregnant women will experience symptoms of morning sickness to varying degrees. Morning sickness most often occurs during early pregnancy, usually during pregnancy