The term “aunt” generally refers to a woman’s menstrual period. There are many reasons for vomiting during menstruation, such as pregnancy, prostaglandin secretion, gastrointestinal diseases and so on. 1. pregnancy: some women who are pregnant have a small amount of bleeding when they come to menstruation, vaginal bleeding is not really menstruation, this situation belongs to the bedtime bleeding, bleeding time is short, the amount is small, usually without treatment is normal, but to exclude the possibility of ectopic pregnancy. 2. Excessive secretion of prostaglandins: When menstruation occurs, the prostaglandins produced by the endometrium can stimulate the smooth muscles in the organs of the body, causing contraction of the smooth muscles, stimulating the gastrointestinal tract and producing nausea and vomiting, usually accompanied by dysmenorrhea. 3. Gastrointestinal diseases: due to the decline in immunity during menstruation, or chronic gastrointestinal diseases, due to dietary disorders is easy because of gastrointestinal inflammation acute and chronic attacks, nausea and vomiting, diarrhea, constipation and other symptoms. Menstruation want to vomit may also exist for other reasons, need to go to the hospital for a clear diagnosis, under the guidance of the doctor to carry out formal examination and treatment, not self-medication, so as not to cause adverse consequences.