Are evaporation lines bold?
How dark or light is an evap line? An evap line is a faint streak that's so light it may look gray or almost colorless. It's not as dark or bold as the control or positive result lines.
Waiting for the results of a pregnancy test can be agonizing. If the result shows a colored line, even a faint one, then the test is likely positive. If the results show a faint, colorless line, then this may be an evaporation line.
Evaporation (Evap) Lines
Evaporation lines are considered false-positive results. Unlike a faint positive result, which will result in a light pink or blue line, an evaporation line does not activate the dye in the pregnancy test, so it may show up as a colorless or translucent line.
Evaporation Lines
The easiest way to differentiate between a positive test result and evaporation line is to check your test within the allotted time. A true positive will appear within two to 10 minutes, while urine won't dry and form streaks until some time later.
Evaporation lines are colorless streaks, not actual lines. They typically appear if a person waits for longer than the suggested time to read the test result.
These tests are 97 to 99 percent accurate. But sometimes, the results are confusing. Some pregnancy tests involve two lines: a control line and a test line. The control line appears on every test, but the test line only appears if there are levels of the pregnancy hormone in your urine.
As the test dries and the urine evaporates, this caught ink is pulled to the surface and becomes darker. This is why the most important rule for getting a true positive pregnancy test is: do not read them after the allotted time!
Evaporation lines on pregnancy tests are generally colorless, but not always. There are some evaporation lines that do have color—either a light blue or light pink. The color, however, is very faint and not as dark as the color of the control line.
On a true positive pregnancy test result, the test line will be the same thickness as the control line. On the other hand, evaporation lines will usually be thinner than the control line.
If the pregnancy test kit is kept for too long and the urine begins to dry out, the evaporation line will appear as faint pink or blue. It may appear if the test is performed too soon or if the hCG levels are quite low, resulting in a false positive.
Can a thin blue line be positive?
Any positive line, no matter how faint, means your result is pregnant. Levels of hCG in your body will increase over the course of your pregnancy. If you test early, your hCG levels may be still be low and you'll see a faint positive line.
Unfortunately, evaporation lines will not disappear, even when you try to remove them with water. If you are not confident with the pregnancy test result, it's highly recommended that you take another test, taking care to follow the instructions properly, to avoid a false positive pregnancy test result.
Should Pregnancy Test Lines Get Darker? Although hCG levels increase exponentially during early pregnancy, that doesn't mean that the pregnancy test line will necessarily get darker as each day passes.
Sometimes, as the ink moves across the screen, a little bit of ink will accidentally get caught in the indent line. As the test dries and the urine evaporates, this caught ink is pulled to the surface and becomes darker.
The key way to tell the difference between an evaporation line vs blue dye positive lines is to see whether the line gets thinner. If it stays thick, it's more likely to be positive, but if it gets thinner, you could be looking at an evap line.