Pregnancy Test Faint Lines and Evaporation Lines

The Two Big Pregnancy Test Questions:
1) How Early Can I Test for Pregnancy?
2) What Does a Faint Line Mean on a Pregnancy Test?

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How Early Can I Test for Pregnancy?
One question women frequently ask when trying to conceive is: How long do I have to wait before I can take a pregnancy test? Though hCG is produced at different rates in different women, there are general timelines for deciding when to test. However, when testing on the early side, do not rely on one test for conclusive results - especially a negative result: the hCG threshold for displaying a positive result on a home pregnancy test may not yet have been reached.
Early Detection Pregnancy Tests
When a woman becomes pregnant, the amount of hCG in her system should be around 25 mIU at 10 dpo (days past ovulation), 50 mIU at 12 dpo, 100 mIU at around two weeks dpo (these are averages that may deviate among different women). Test sensitivity equates with early-detection - and the lower the number, the sooner a test can detect pregnancy. At 20 MIU test sensitivity, you can begin testing at 7-10 days post ovulation, though the earlier you begin testing, the higher chance you have of getting a false negative. carries early-detection pregnancy tests capable of detecting just 20 miu/ml hcg.
Here, implantation of the fertilized egg needs to take place before hCG is produced by the developing placenta, and that generally occurs at 6-10 dpo. If you decide to test early, make sure you perform a few follow-up tests every other day using first morning urine. Your hCG levels should rise exponentially, doubling every 2 days - which means that the follow up tests should eventually detect pregnancy if you are, in fact, pregnant.

For earliest detection of pregnancy, use first morning urine, as this urine sample contains the most concentrated amount of hCG. If using first morning urine is not feasible, avoiding urination for several hours before using a pregnancy test.
 Faint Line
A faint color band in the test area of a pregnancy test indicates, in most circumstances, a positive result for pregnancy.
However, a faint line appearing after the designated reaction time of the test may be an "evaporation line".
What Does a Faint Line Mean on a Pregnancy Test?
On a pregnancy test, a faint test line - or color band - is usually indicative of a positive result, as long as it's read within the time frame - or reaction time of the test (usually at 5-10 minutes). If you perform the pregnancy test properly and read results within the recommended time frame, then a faint or weak color band in the test area is very likely a positive pregnancy test.

Evaporation Lines
Evaporation lines, however, can confound results if tests are not interpreted within the clinically recommended time frame. An evaporation line develops when the urine on the test area begins to dry, leaving a faint, usually colorless line. Evaporation lines appear to show up (or not show up) as a result of the composition of the particular urine specimen - and they may appear on any test regardless of brand.

Explanations for Faint Positives
  • Testing Too Early: If you test too soon, hCG may not be at a sufficient level for test detection. See the section above on determining when to take a pregnancy test.

  • 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 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.

  • 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.

  • Chemical pregnancy: Sometimes an early pregnancy is detected - followed by negative test results. A chemical pregnancy means implantation takes place (hCG is produced for a short time) followed by a miscarriage (generally, before any other pregnancy symptoms are detected).

  • Evaporation Lines: Always read your test results within the test reaction time (usually 5 minutes) as evaporation lines can develop as the urine dries on the test area. Evaporation lines appear to show up (or not show up) as a result of the composition of the particular urine specimen - and they may appear on any test regardless of brand.
Remember, a pregnancy test does not function like "light switch" - and just turn on: different hCG levels will produce different gradients of color bands (from very light, faint lines early in pregnancy to dark, rich color lines later on as hCG develops).
Read More About Pregnancy Tests
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i took a pregnancy test because i was 4 days late and it showed neg. out of curiosity i checked it again the next day and it said positive. the same thing happened with another one that i took. i read an article that said no matter how long it sits ONLY the hcg hormone can detect it and it will travel up the stick as long as the tests are still wet. they both still say positive and they are not grey or discolored. they are both blue lines. went to the doctors today and their test said neg but had blood drawn. will find out Monday what the results are. also on day 4 of missed period i had a pain in my lower abdomen and thought i was starting, turns out it was just spotting? this would be my first pregnancy and I'm just getting different answers. can anyone give any insight to this.

Something similar happened to me today. I took a test and first, only one line appeared. After about 6 minutes, a faint pink second line started to appear, and it was more clear after 10 - 15 minutes. I don't know.what go think ... I am only a week late and we've beeen trying. or .about a year. Thanl

I had a d&c 4weeks ago for a blighted ovum, Ive been testing positive for two weeks now, is it a new or old pregnancy??

please help.... I took a pregnancy test at 12am and I was sure it was a negative result but then after 10 mins I looked at the test again out of curiosity and it had a second DARK red line indicating a positive result so I took another test at 7:30am and the same thing happen and these were two completely different brands of pregnancy testes. so I waited until the next day to test again but received a negative result. so my question is could this be a evap line or could I be pregnant??

hi well I took a test the other day and the one line came up dark and I didn't see any other line so I sat it down and left it in the trash well today my husband saw it and it had a faint blue line on it, I am not sure if its still a positive test even though it sat until today its not a gray line its Blue I mean u can see the color its just very faint so am I pregnant or not I know the color wont show up unless you have the hgc hormone in your urine so can some one please help

A few weeks ago I bled light pink for a day, and then I missed my period and went to the drs and had a pelvic exam and she said nothing about pregnancy, but I took a test today and in the window is one bold line, but just outside the window if I hold it at an angle I can see another line...both are pink, am I pregnant??

My periods always start on the 1rst of the month it is now the 21st.. On the 18th i took a preganacy test at 5am and it came up right away really dark.. Then yesterday the 20 my partner wanted me to take another just to make sure. He bought frist response i think.. I took the test that night it came up positive but, a real faint one. Me and him dont want to tell anyone till me are sure. Does this mean i am pregnant? because, i think it does but, i am not sure... When I was 16 the tests did this before and i had to get the blood work done to find make sure I was 100%... Ughh. All we want is a baby so bad.

I did a pregnancy test few weeks ago and I got a faint line. I did the test again after a week but the line is pinkish it does not get bold but it is clearer that the line on the first test. I am really worried, am I pregnant or did I have a chemical pregnancy ? please assist a sister out!

So I have taken about 8 tests. This is my 4th child and I know what my body does when pregnant. This had never happened before. Two digital says not pregnant, 2 first response and a EPt have come back with a bright control line and a weird test line. Top and bottom are pink and the center is clear/indent line. I have never encountered this before.
Ps: I'm on CD26, 13dpo and I'm a test break opener.

I usually have 35 day cycles, my last period was on 10-24-13 I took a test this morning it read negative and the indicator line box was blank. I feel and look pregnant. Should I re-test?

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