A pregnancy test is a tool used by women to check if they are pregnant. The principle of the test is based on the human chorionic gonadotropin in human urine. There are three types of pregnancy test results: 1. not pregnant: a control line is shown, indicating that there is no pregnancy. 2. pregnant: there are two lines, i.e., both the control line and the test line are colored, and the test line is clearly visible, indicating that the pregnancy has occurred. If the control line is obviously clear and the test line is light, it means that you may be pregnant, use a new pregnancy test stick every two days and re-test with morning urine.3. Invalid: no control line appears within 5 minutes, it means that the test is invalid or failed. Pregnancy test stick test there is a certain error probability, if necessary, through the blood HCG examination, comprehensive analysis, clear diagnosis.