The sudden disappearance of early pregnancy reaction may be caused by normal physiological factors or pathological factors such as fetal arrest, which should be analyzed specifically according to the time of disappearance and then combined with relevant examinations to make a clear diagnosis. Common causes and treatment methods 1. Physiological factors: Early pregnancy reaction is mainly caused by the rapid increase of hormones in the body, which usually lasts for 2-3 months. After 8-10 weeks of pregnancy, chorionic gonadotropin will reach its peak and will gradually decrease after a period of smoothness, so the early pregnancy reaction of most pregnant women will disappear naturally in the 12th week of pregnancy. At this time, most of the fetuses develop normally and the early pregnancy reaction is reduced, so pregnant women can relax and continue to have regular maternity checkups; 2. Pathological factors: mainly due to insufficient maternal hormone secretion, which causes the embryo to stop developing and causes a sudden drop of chorionic gonadotropin, which leads to the disappearance of early pregnancy reaction, usually accompanied by vaginal bleeding. You should go to the hospital for ultrasound examination in time to make a clear diagnosis and choose to continue to observe the symptoms under the guidance of a professional doctor or to carry out medical abortion to ensure the safety of the mother. In addition, pregnant women in early pregnancy should pay attention to keep their vulva clean, prohibit sexual intercourse and excessive activities, and eat a light diet with small and frequent meals. Pregnant women should also pay attention to keep a calm state of mind and avoid excessive stress.