The color of the pregnancy test paper becomes lighter

Early pregnancy test strips are a product used to test whether you are pregnant. Many women use early pregnancy test strips to preliminarily determine whether they are pregnant. Many women will find that the reading on the pregnancy test paper becomes lighter day by day. This is an abnormal phenomenon. Therefore, women need to go to the hospital for examination in time to see if they have threatened miscarriage, biochemical pregnancy or ectopic pregnancy.

1. The early pregnancy test paper is getting lighter day by day

If you use an early pregnancy test strip after you become pregnant, the color may gradually darken. If the color of the early pregnancy test strip becomes lighter than the original test, this is abnormal. If there is no quality problem with the early pregnancy test strip, it may be threatened abortion or biochemical pregnancy, or it may be ectopic pregnancy, etc. It is recommended to go to the hospital to check the human chorionic gonadotropin in the blood, because sometimes the pregnancy test stick is not very accurate.

Due to the influence of quality and interference from other factors, false negative or false positive results may sometimes occur. So this is uncertain, and it is most accurate to go to the hospital for a blood test. If the pregnancy is normal, hcg will double every 1.7 to 2 days.

2. Principle of Early Pregnancy Test Paper

The detection reagent uses the principle of immunochromatographic double antibody sandwich method to make HCG detection test strips, which can measure HCG in urine samples within 3 minutes. During the test, when the urine sample is siphoned through the colloidal gold-labeled antibody, an antigen-antibody colloidal gold complex is formed. The complex continues to crawl and passes through the coated anti-HCGα subunit Mcab to form a double antibody sandwich colloidal gold complex, which appears as a color band at the coating line. The excess colloidal gold antibody continues to crawl and forms a colloidal gold immune complex with the sheep anti-mouse control line, which appears as a color band. The HCG colloidal gold test kit uses a double antibody sandwich one-step technology and colloidal gold as an indicator marker to detect the HCG concentration in urine to confirm whether a woman is pregnant. The test strip is a reliable indicator to assist clinical determination of pregnancy.

3. Early pregnancy test results

1. Negative: A purple-red line (control line C) appears in the test area, indicating no pregnancy.

2. Positive: Two purple-red lines appear in the test area (control line C and test line T), indicating pregnancy. The color intensity of the test line at different stages of pregnancy changes with the change of HCG concentration.

3. Invalid: No purple-red line appears in the test area or only one purple-red line (test line T line) appears in the test area, indicating that the test failed or the test paper is invalid and should be retested.