The earliest and most characteristic signs of early pregnancy include: 1. The earliest and most characteristic sign is that the usual regular menstrual flow no longer comes on time and the symptoms of menopause appear. 2. Some women in the early stages of pregnancy will have obvious symptoms of physical tiredness, fatigue, dizziness, drowsiness, etc. 3. 4. There may be symptoms of frequent and urgent urination, nausea, vomiting, loss of appetite, changes in eating habits, and other digestive symptoms. Women who have a regular sexual life and do not take effective contraceptive measures should consider the possibility of pregnancy if the above reactions occur and go to the hospital in time to get a clear diagnosis.