Can EVAP lines have color?
How to identify an evaporation line on a pregnancy test? In early pregnancy, there may be very little hCG in the urine, and the positive line may be faint. But even a faint positive line has color, and this distinguishes it from an evaporation line, which is colorless.
It's also important to note that while an evaporation line appears faint, a faint test line on a pregnancy test doesn't automatically suggest an evaporation line. A faint positive test line can also appear if you take a pregnancy test shortly after implantation when your hCG level is low, or if your urine is diluted.
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 are generally more muted than the control line. On a pink dye test, an evaporation line may look like faded gray. On a blue dye test, the line can appear as gray or even a lighter shade of blue.
What Color Are Evaporation Lines On Pregnancy Tests? Evaporation lines are usually colorless. But, some lines may appear light pink or light blue. They are lighter than the control line and may sometimes appear greyish.
An evaporation line on a pregnancy test is a faint line (or rather, mark) caused by a test reaction that occurs when the urine evaporates, or when the test gets wet. Sometimes this line appears in the test window, making it look like a faint positive result. Evaporation lines are colorless streaks, not actual lines.
An evaporation line on a pregnancy test is basically a false positive. While true false positives and false negatives are fairly rare,1 the evaporation line is the closest most women will come to having an error on their pregnancy tests.
Evaporation Lines
A true positive will appear within two to 10 minutes, while urine won't dry and form streaks until some time later.
“This is simply due to your urine evaporating and is not a positive test.” That's why you should read the results when your product recommends and then toss the test in the trash to avoid confusion — and false hopes. For the most part, pregnancy tests don't get darker as they go along.
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.
Can an EVAP line be as thick as 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.
Look at the line carefully — it may not be as bold as the control line, but as long as there is a distinct color to it, it's considered positive. If it's gray or colorless, it's most likely an evaporation line.
A test line can be faint pink if your urine is diluted or it's very early in your pregnancy. Not-to-worry, though. Even a faintly pink-colored test line indicates a positive result. Simply put, if there is color on the test line, it's time to check in with your doctor to confirm a pregnancy.
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!
In a healthy pregnancy, hCG levels double every 2 – 3 days. This means that if you take your first pregnancy test very early in pregnancy and get a faint positive, you should expect to get darker positives if you test over the next few days/weeks.
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.
Different Line Colors
When taking a pregnancy test, any line in the test indication area is considered a positive pregnancy test, even if it is lighter than the control line. The darker line is usually the control line. Sometimes this second line is so faint, you can barely see it.
The test line can be darker than the control line once your HCG level rises; it's normal and nothing to be concerned about.
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! The results are only accurate in the time frame specified in the instructions.
What does a line as dark or darker than the control line mean? When your test line is as dark or darker than the control line, the test is positive, and you'll likely ovulate within 24-48 hours! If you want to get pregnant this month, now is the time to have sex.
What does a faint line look like on a pregnancy test?
Each pregnancy test is different, with some brands using a red dye and others, like Clearblue, a blue dye. For a red dye test, a faint line will look light pink, whereas a blue dye test will produce a light blue line.
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.
In many cases, when you are using a First Response™ test, the test line may be a fainter pink than the control line, which is sometimes quite dark. A test line can be faint pink if your urine is diluted or it's very early in your pregnancy. Not-to-worry, though.
When the positive test line on a pregnancy test is stronger than the control line, it is called a “dye stealer test.” Pregnancy tests detect hCG. When hCG levels are high, the positive test line can be so strong that it steals the dye from the control line, making the control line very faint.
Pregnancy test results should get darker early on as a pregnancy progresses. If your pregnancy test results seem to be getting lighter, it could be because you tested after drinking water and your urine was more diluted. Or, the first test result could have been an evaporation line and not a positive result.
This is because relatively large amounts of virus need to be present for the antibodies in the test to react to the viral proteins. A faint, slow-to-appear line could still represent high levels of virus, meaning that if you can see any line at all, you are still highly likely to be infectious.
A faint line on an ovulation test strip does not indicate a positive result, i.e., that you are about to ovulate. You have to make sure that the line in the test window is darker than or at least the same color intensity as the control line.
Evidence shows that this time of increased fertility usually spans 6 days, starting approximately 5 days prior to ovulation and ending on the day of ovulation itself. The 6-day fertile period is affected by: The lifespan of the egg, which is up to 24 hours after ovulation. The lifespan of sperm which is more variable.
The ovulation predictor test looks for a hormone called LH or luteinizing hormone in your urine. LH hormone surges 24 to 36 hours before you ovulate. If the surge occurs first thing in the morning, it can take 4 hours for the hormone to be detected, so your first morning urine may miss it.