Here's what each signifies on a pregnancy test, and how to tell the difference. Verkkocould it be a faint positive or an evaporation line? Many home pregnancy tests have two lines: A control line and a test line. The control line will. Verkkounderstand the difference between a faint line on a pregnancy test that means you're pregnant and an evap (evaporation) line that is colorless and. Verkkoan evaporation line may appear if you wait too long to check your results — meaning your pee is dry. Most tests ask you to read your results before 10. If you're second test is negative after a positive result, you may have mistaken an evaporation line in the first test as a positive.
