IC HPT = Internet Cheapie Home Pregnancy Tests. Yes we sell them so cheap online, they even earned their own initial on TTC forums LOL.
I guess the question is why they sell them so expensive in shops. I happened to check some packages out at safeway (woolworths) last weekend. One of them actually stated "made in USA". W.O.W. shock horror! It is like hitting a jackpot. How often do you come cross goods in supermarket that are made in USA? I guess you pay the price for them as well. :) anyway back to the topic.....
Evap Line is short for evaporation line. It is a shadowy colourless line (or look like a dent / watermark on the strip) appears where the BFP (big fat positive) line should be. If you have countless HPTs under your belt, you probably have already encountered several evap line tests.
Evap Line is not a BFP Line! Any BFP line should be coloured, pink or blue, regardless of how faint or dark they are.
What cause the Evap Line? There isn't enough, if any, proper research done on the Evap Line. So you can assume it isn't something serious. Browsing various websites and forums, there are several theories out there. The one that makes the most sense to me is that the invisible line is always there. When the urine soaked test starts to dry up, it may leave watermark. That is Evap Line. It has nothing to do with the quality of the test. It can happen with any brand not just IC HPT.
Huh? Always there? YES. A bit of HPT anatomy. That positive line is always there, invisible, filled with certain material and colour dye. When the concentration of hCG in your urine reaches the detectable level, it triggers the chemical reaction and release the dye. Hence you see the pink or blue line when you get BFP.
So how can we avoid the Evap Line? Not sure we can avoid it 100%, but here is something we can do.
Follow the instructions!!! Don't dip the stick passing the MAX line. Don't soak it for longer than instructed (I am guilty of that). Wipe off the excessive urine on the surface before laying it flat for result (I am guilty of that). And don't read the result outside the said time frame (I am very very guilty of that haha).
We all know it is the concentration level in your urine that matters, not how much wee is absorbed by the test. But I just can't help having my test totally saturated with urine. I guess it is not a crime to have your test saturated with urine, or to read the test way pass the time frame. Just keep in mind these are sort of things that may increase the chance of getting an evap line.
And again, a line is not always a line. Only a coloured line is a positive line, faint or dark.