The most obvious symptom of a biochemical pregnancy is the presence of vaginal bleeding similar to menstruation. A biochemical pregnancy is caused by unsuccessful fertilization of the fertilized egg, without a history of significant menopause, and can be confirmed by a blood HCG (human chorionic gonadotropin) test, although the HCG value is usually not high. Vaginal bleeding will then occur during or slightly delayed by the menstrual cycle and will be relatively heavier with a slightly prolonged menstrual period, after which the blood HCG can be rechecked and reduced to normal. The occasional occurrence of a biochemical pregnancy in the early stages of pregnancy is not necessary to be too anxious, we should pay attention to appropriate rest, relaxation, appropriate increase in nutrition, under the guidance of the doctor in the next menstrual period to continue to prepare for pregnancy. However, if it occurs repeatedly, you need to go to the hospital, identify the cause under the guidance of the doctor and give active treatment.