The lightening of pregnancy test paper represents the short duration of pregnancy, pre-miscarriage or ectopic pregnancy, and other causes caused by other factors. 1. Short pregnancy: women use pregnancy test paper to measure two lines, but one line becomes lighter indicating a weak positive, may be due to the short duration of pregnancy, the test time is too early, the HCG content in the urine is not high caused by the test, can be re-tested in a few days, usually will appear strong positive results. 2. Pre-eclampsia: If you have been diagnosed with pregnancy after pregnancy test paper color becomes lighter may be related to pre-eclampsia, there are signs of miscarriage or the embryo stops developing, the body’s HCG is no longer doubled rapidly, but will decline, will lead to test paper becomes lighter, usually also appear abdominal pain and vaginal bleeding. It is necessary to combine blood HCG and progesterone test to confirm that the embryo is well developed and then give progesterone and vitamin E to protect the fetus treatment. 3. Ectopic pregnancy: when ectopic pregnancy occurs after pregnancy, the fertilized egg can’t grow normally when it is deposited outside the uterus, and the HCG in the body is slow to double, and the phenomenon of the test paper becoming lighter will also occur. The diagnosis can be confirmed by combining ultrasound and blood HCG examination, giving mifepristone and methotrexate tablets for conservative treatment, or surgical treatment as soon as possible. 4. Other reasons: the use of substandard test strips or drinking too much water before using the test strips to dilute the urine, as well as the occurrence of biochemical pregnancy after pregnancy, etc., can also lead to the test strips become shallow, and need to improve the relevant examination to clarify the reasons for the test strips to become shallow, and then symptomatic treatment. In addition, the specific use of the above drugs should be under the guidance of a doctor, do not take on your own.