A pregnancy test is a tool to test for pregnancy and can be bought by women themselves at pharmacies. It proves pregnancy by measuring the level of human chorionic gonadotropin in the urine, and if two lines appear, pregnancy is indicated. If women use pregnancy tests for self-testing, the accuracy of the test results can generally reach 50%-90%, and the accuracy of the regular brand pregnancy test is about 85%-95%. In case of irregular menstruation, the reliability of pregnancy test using pregnancy test stick is relatively low because when menstruation is irregular, if you are pregnant, the content of human chorionic gonadotropin in urine is low and sometimes it may not be detected, resulting in false negative. In addition, whether it is a test paper or a pregnancy test, it can be detected as early as 8 days after fertilization. If you want to be more accurate, you should wait until 11 days after fertilization. It is best to use morning urine for testing to avoid drinking too much water, which may dilute the urine and cause inaccuracy. Content source: Dr. You Lai