If the second line of the morning pregnancy test is light, it is often caused by the following reasons: 1. drinking too much water before leaving the urine, which causes dilution of the urine, so it appears weakly positive; 2. because the number of days of menopause is relatively short, the HCG level in the urine is not yet very high, so it appears weakly positive; 3. in clinical cases of ectopic pregnancy, it will also appear weakly positive. It is advisable to do another test with morning urine in 3 or 5 days without any symptoms, and most of the 2 lines will be the same color by then. If there is still a lighter line, it is recommended to go to the hospital as soon as possible to have a blood test for HCG, which will definitely rule out the possibility of ectopic pregnancy in clinical practice.