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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My girlfriend just found out she's pregnant. We had sex for the first time on 03-21-12 she found out she was pregnant on 04-06-12 this is exactly 3 weeks. Is this soon enough to know or does it take longer? The doc estimated she's 5 to 6 weeks based on the data she provided.

I was suppose to start on March 19th and I still haven't started yet. I've been eating and going to the bathroom more frequently. I tend to fall asleep even when I don't think I'm tired (my boyfriend has even started to notice that I'm being extremely tired lately). I feel bloated, have light cramps in the lower part of my stomach, but I would be able to tell if they were period cramps. I've also been having really sore breasts, really really sore and little back pain. My moth has also watered like I'm about ready to get sick but I haven't actually gotten sick yet. Could I be pregnant? I need answers! Please...

my wife tried 2x of pregnancy test and it indicate as Positive 1 thick line and 1 faint line those 2 test are all same in one testing only,but after a few days my wife got a small quantity of menstruation bleeding and its gone,I just like to know if my wife is pregnant?

i had sex on the 6th and had an emergency contraceptive pill on 7th my mense is due on 15th what are my chances of risking pregnancy???????????

am just a few hours away from my mense date vry nervous about taking a preg test tomoro morning .i had sex on 6 and my mense is on 15 do u think its too early to go for a preg test or should i wait for another couple of days????????????????

Need some advice...I'm 4 days away from my expected period and took an early detection test today. I know to not look at it after a certain amount of time but I just looked once more about a half hr later and a noticed a faint blue line going vertically, which would indicate a positive. I know about evaporation lines but I've heard that those lines are usually grey in color? So anxious! Any advice??

so i was wondering if this is a evap line or faint positive my display pic is the test pic since i cant uploadpics to show you any help would be nice thanks username jbarbe

i took a test on feb 19 and it was negative.. so i then took one on march 2nd of 2012 and it was postive.. am i pregnat if so how far am i giving those dates. my breast are no longer super sensitive but im super tired and im not nausea.. how far do you think i am? thanks

@Angela kinda....... I def think u should retest on mon.....I know that's going to seem like forever! Usually the tests say to disregard the results after a certain amount of time. Did you look at it after 5min? Even if u see a faint line after 5 min or so it is a positive! A line is a line......after an hour lapse of time though it could b the evaporation line, just won't know until u test again!

@Confused.... I'm in the same situation right now! I am 4 days away from my period and "feel" pregnant. This is my 5th pregnancy (I have twins and a son and had 3 miscarriages). I got a faint line....very very faint, wondering if my eyes were just playing tricks on me! Wondering if u tested again and the results?

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