I see a faint line on my home pregnancy test, am I pregnant? Home pregnancy tests determine pregnancy through the detection of the hormone hCG (Human Chorionic Gonadotropin) in a woman's urine. In technical terms, hCG is a glycoprotein hormone secreted by the developing placenta shortly after a fertilized egg has been implanted in the uterine lining. The appearance of hCG soon after conception, and its subsequent rise in concentration during early fetal growth, makes it an excellent marker for the early detection of pregnancy. Pregnancy tests come in two common formats dip tests and midstream tests. To use a pregnancy dip test strip, you fill a clean, dry container with urine and hold the test strip in the container for several seconds. With midstream tests, you simply hold the test in your stream of urine. Both test formats are equally reliable. Though they all function by the same principle, you need to read the instructions for the use of your pregnancy tests carefully. With most home pregnancy testing products, the "reaction time" of the test is a minimum five minute interval to verify a negative result for pregnancy. Generally, at three to five minutes, you can interpret the test results. To be accurate, the test results should be read within the reaction time of the test, which is usually at 5-10 minutes. Manufacturers also recommend that you should not read tests after a designated time period, as most test brands have the possibility of developing evaporation lines. Once the reaction time of the home pregnancy test is complete, color bands will either appear or not appear in the test region of the strip or midstream unit. All tests have a "control" color band or color line that indicates whether the test is working or not. The "test" color band indicates a positive or negative result. Assuming that the home pregnancy testing procedure has been followed properly and the results have been interpreted in time, a faint line in the test region may be read as a positive result, though it's a good idea to verify any result with an additional test 24-48 hours later. A second faint line on a home pregnancy test is usually confirms as a positive result, indicating conception. Why are these faint lines caused? Here are some of the most probable reasons for the formation of faint lines in early pregnancy tests. 1. Testing Too Early: If you test too soon, less than 8-10 of conception, hCG may not be at a sufficient level for a strong positive result. 2. Low Test Sensitivity: Different tests detect hCG at different levels, from 20MIU to 100MIU or more. 20 MIU tests will display a faint line when hCG levels are at 20 MIU, while less sensitive tests will display a negative result. At 50 MIU levels, a 20 MIU test will show a stronger color band while a 50 MIU test will show a very faint band. Visit our pregnancy test comparison chart to find out what level of hCG many of the popular pregnancy tests detect. 3. Dilution of Urine Specimen: Urine specimens may be diluted due to frequent urination or consumption of liquids. First morning urine is recommended for pregnancy testing as it contains the most concentrated presence of hCG. 4. Chemical pregnancy: A chemical pregnancy means implantation takes place and hCG is produced for a short time. However, this is followed by miscarriage before any other pregnancy symptoms are detected.