An evaporation line on a pregnancy test is due to the evaporation of urine in the test window where the antibody strip is located. This will result in a colorless line that may be mistaken for a positive result. Usually, the evaporation line is more grey than pink or blue. It may appear like a shadow.
What is an EVAP line on a pregnancy test?
If the indent line is grey or has color (however faint), then it is considered as an evap line. Dye runs are smudged lines that show up in the area where a true test line should be. This is a false line. It may look like a promising indication of pregnancy, but it isn’t. It is also not an evap line. A true test line should be solid, not smudged.
Do clear blue pregnancy tests have evaporation lines?
Unfortunately, yes. Clear blue pregnancy tests can rarely result in evaporation lines. Although evap lines can be seen in both pink and blue dye strips, it is notably of higher incidence in the blue dye strips due to close resemblance of the colors – faint blue and gray.
Why is there a blue line on a pregnancy test?
Ross says it’s because the blue dye test works by using an evaporation line that depends on the evaporation of urine, and that line can be colorless, which is often confused as a positive pregnancy test. “The colorless line is more grey or appears as a shadow instead of appearing pink or blue,” she says.
Do evaporation lines show up early in pregnancy?
Some women may see an evaporation line after five minutes while for others, this line may appear in an hour or so. An evaporation line does not indicate pregnancy and is merely a result of evaporation. Do not make the mistake of considering this a faint positive line. Do evaporation lines have color? Evap line vs. faint positive.
Can an EVAP line be blue?
While an evaporation line can appear on a pink or blue dye test, many frequent testers on popular online pregnancy and fertility forums adamantly argue that blue tests are more prone to these deceptive shadows.02-Jun-2020
Are EVAP lines blue or GREY?
The key difference is that an evaporation line is colorless (which may appear as a faded gray on most tests). This is an important distinction because if your test is positive, the line that tells you it's a positive result will appear in the same spot as the evap line—but will have some color to it.
What Colour are EVAP lines on clear blue?
On a blue dye test, the line can appear as gray or even a lighter shade of blue. (Note: For some reason, anecdotally, many mamas find that blue dye tests are more prone to evaporation lines.) Sometimes, though, the evaporation line appears as a colorless streak, almost like an indentation.28-Jul-2021
Do EVAP lines have color when inverted?
Saying that ANYTHING pink at all (assuming a pink dye is used) when inverted will turn green. An evap line that's usually grey or whitish will remain a dull color.04-Dec-2021
Does EVAP lines have color?
Evaporation lines are colorless streaks, not faint lines. They typically appear if a person waits for longer than the suggested time to read the test result. An evaporation line can also appear if the test gets wet.31-Jul-2018
Can an evaporation line show up immediately?
2 The evaporation line does not show up until after the pregnancy test reading window of time to accurately get your results. So you will not need to worry about an evaporation line if you read the pregnancy test within the time frame specified in the instructions that came with your test.28-Feb-2021
Is clear blue EVAP line blue?
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. See images below to get an idea of what a faint line can look like.07-Feb-2022
Does clear blue give false positives?
Most home pregnancy tests are reliable, for example Clearblue's tests have an accuracy of over 99% from the day you expect your period, and while it's possible a test showing a negative result is wrong, particularly if you're testing early, getting a false positive is extremely rare.27-Oct-2021
Will an evaporation line disappear with water?
Will an EVAP line washed away? It should be very visible and remain visible even after 48 hours. With most brands of home pregnancy tests, the positive test line never fades away.11-Dec-2021
How long do evaporation lines stay on the test?
Evaporation Lines This usually ranges between a couple of minutes up until 10 minutes later. If you see a positive result beyond this time frame, you may be left second-guessing the results. However, the false-positive reading, in this case, is due to something called an evaporation line.17-Oct-2021
How faint Can a pregnancy line be?
If you check your results within the recommended time frame and see a faint positive line, you're most likely pregnant. On the other hand, if you miss the window for checking the results and you don't check the test until 10 minutes later, a faint line may be an evaporation line, which means you're not pregnant.
How do you know if line is indented?
An evaporation line is a faint line that appears after a negative pregnancy test has dried. Tests that show two line results have what are known as 'indent' lines where the ink pools. One line is for the control line and one is for the positive result (if there is one).
How Does An At-Home Pregnancy Test Work?
An at-home pregnancy test is a simple way to find out if you're pregnant before seeing a doctor. When you schedule an appointment with your doctor...
What Is An Evaporation Line on A Pregnancy Test?
Evaporation lines are common and can occur with any pregnancy test. An evaporation line is a line that appears in the results window of a pregnancy...
How to Identify An Evaporation Line on A Pregnancy Test
Evaporation lines are common on pregnancy tests, but they don’t appear every time. It depends on the chemical makeup of each woman's urine. One of...
How to Avoid Getting An Evaporation Line on A Pregnancy Test
An evaporation line on a pregnancy test appears after the reaction time. Unfortunately, if you let the test sit for a long period, it’s hard to kno...
How pregnancy tests work
Pregnancy testing can be done using blood or urine. Most of the readily available pregnancy tests are urine-based. Although they come in different brands, they all work on the same principle.
Evaporation line clear blue on pregnancy test
A faint and thin streak that appears where the positive line on the strip usually should be is called an evaporation line or commonly known as an evap line. These are formed due to delaying the time of reading the results or wetting the test strip.
What do evaporation lines look like?
If you’re wondering what an evaporation line clear blue looks like on a clear blue test, here is a clear blue evaporation line example marked by the black arrow.
Do evaporation lines disappear?
Evaporation lines do not usually disappear even after 48 hours of testing. They may fade a little over time, but never completely.
Evaporation line clear blue vs positive line clear blue
An evaporation line is like a wet streak on the strip, unlike a positive line that is clearly colored and visibly linear. A positive line is a solid line that can be pink or blue, depending on the kit used.
Evaporation line vs faint positive
A false positive, clear blue evaporation line is not very easily distinguished from a faint positive line. It is common to get confused by an evap line for a faint positive line if you don’t know a clear difference.
Blue dye vs Pink dye Pregnancy tests
The pregnancy tests kits come with strips that have specific dye in them. Once the urine sample is placed, a chemical reaction produces either pink or blue lines to indicate a positive pregnancy test along with the control line used as a reference.
What does an evaporation line on a pregnancy test mean?
An evaporation line does not indicate a positive result. An evaporation line is a slight streak that appears where the positive line on a pregnancy test should be . Evaporation lines are colorless streaks, not faint lines.
What is the line on a pregnancy test called?
A test may show a small streak where the positive line should be. This is called an evaporation line. An evaporation line does not indicate pregnancy. If this type of streak appears, ...
What happens if you get a negative HCG test?
If the result is negative, it may be a good idea to take another test in a few days, to give hCG levels a chance to rise. Very few medications, including fertility drugs, may cause false positives. Otherwise, a positive result followed by a negative result a few days later could mean a very early pregnancy loss.
What does it mean when you see a positive pregnancy test?
If a person sees an evaporation line, it means that the test is negative, or it was taken too early in the pregnancy to show a positive result.
How low is hCG on day 14?
By day 14, hCG levels are typically around 137 mIU/ml. For some women, however, they can be as low as 45 mIU/ml. Because hCG increases so rapidly in the early days of pregnancy, getting the day of ovulation wrong by 1–2 days can affect the result of a pregnancy test.
How long does it take for a pregnancy test to show positive?
The line appears within the period specified on the instructions, which is usually 3–5 minutes. A woman has taken an early-result test at least 11 days after ovulation.
Why does a woman have an evaporation line?
An evaporation line does not indicate that a woman is pregnant. These lines often occur when a person has checked the result too late or taken the test incorrectly. When an evaporation line appears, it is best to take another test for an accurate result.
What color are pregnancy evaporation lines?
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. The evaporation line can also sometimes appear greyish.
What does it mean when you see a faint line on a pregnancy test?
A faint line means a positive pregnancy if it appeared during the reaction time. If you see a faint line after 5 minutes of taking the test, then it is an evaporation line and IS NOT an indication of pregnancy.
Why does my urine show faint lines?
However, a faint line could also be an evaporation line, which, according to Dr. Peter Rizk, MD, "is caused by evaporation of the urine in the result window of a pregnancy test. It develops after the recommended reaction time frame (approx. five minutes) when the urine on the test area begins to dry, leaving a faint, colorless line.
What does a second line of pregnancy test show?
Dye will accumulate in this area, and a second line will appear, indicating a positive pregnancy. If no hCG is present, then there will be nothing on the antibody strip to react to the dye. The second type of home pregnancy test uses a test device and a urine collection cup.
How long does it take for a pregnancy test to work?
Most home pregnancy testing kits require a minimum of five minutes of reaction time. This is the time needed in order for the chemicals in the test kit to react with the hCG hormone in a woman's urine. hCG, or human chorionic gonadotropin, is one of the early hormones produced when a woman is pregnant.
How long after ovulation can you test for pregnancy?
Some women use a home pregnancy test even before a missed period. The best time to test is at least seven to 10 days after ovulation, or at least three days after your missed period. Testing earlier than that can result in a false negative or a faint positive reading. If you get a faint positive line, repeat the test after a few days. Use the first urine in the morning. This urine sample is concentrated and will likely have a higher level of hCG, which will give you a more accurate result.
How long after a pregnancy test is negative?
If the test turns out negative within 5 minutes of testing, then it is negative.
What does an evap line look like?
What I didn’t realize was that an evap line can look exactly like a positive test result.
How do evap lines form?
Evap lines can form when the ink used to signal a positive pregnancy is pulled into the results window by drying urine, or even just from the dry urine showing up as a faint gray, or shadowy line. It’s important to note that evap lines are different from false positives, even though the rollercoaster you get sent on can be the same.
Can you retest if you have an evap positive?
You can always retest, and if you’re like me and rocking a trusty IUD and NEED TO KNOW THIS VERY SECOND if that evap line is a sneaky positive, you can go to the doctor and get the blood test. But any result read outside of the testing window is invalid.
Can you pee on your fingers while taking a HCG test?
Urine travels across a test strip where it has a chance to interact with chemicals that will signal if hCG is present. The tricky part, aside from not peeing on your fingers while you’re doing it, is that you can’t always control for every variable, like for example tiny variances in the individual test strips, or how the urine dries on the paper. ...
What is wrong with blue dye pregnancy tests?
Taking a pregnancy test is super stressful, and the possibility of false positives, evap lines, and potentially false negatives make it even worse.
What is the most sensitive test for pregnancy?
The most sensitive test you can get would be a blood test at the doctor, she says, where they measure the hCG levels. Otherwise, “Using the First Response Early Result is also a reliable and accurate over-the-counter pink dye test that can be used to detect pregnancy,” she recommends.
Is it bad to have a pregnancy test when you are pregnant?
There is nothing worse than a pregnancy test telling you that you’re pregnant when you're actually not — talk about heartbreak and an emotional letdown. Dr. Sherry Ross, OB-GYN and women’s health expert at Providence Saint John’s Health Center in Santa Monica, California, agrees and tells Romper that the blue dye tests are definitely more ...