What Causes Evap Lines?

[LovingLimes]

Has anyone wondered what causes evap lines? It seems like when I get them, they are always on the same day, or same time frame. I was thinking maybe if you eat a lot of salt, that can cause it? Or maybe if it's during a specific time of your cycle. I was even wondering if it has to do with how long you dip the pg test in the urine. Anyway, why do some tests have them and some don't? Has anybody else wondered this?

 

[Babybump87]

I thought it was something to do with moisture from the urine when it hits the test ?

All I know is they are so annoying I had three evaps in one month . Two on the same brand and one a different brand.

 

[jellybeanxx]

I thought they had something to do with where the line would be if there was enough hcg to make the dye stick to that part. Evaps tend to lack colour don’t they? So when the test dries it, you can sometimes see where there would be a line.