I've had 2 problems with these tests. First time around I got a positive and then went to my doctor on the same day, and the test was negative. When I called the helpline they said I must have had a miscarriage (not possible, since I had one before and would have recognized it) or an ovarian cyst (also not possible). So basically I am the .1% that is for an error. I did not think you could get a false positive. I was so devastated as we had been trying for a while. Second time around I bought the drugstore brand. I got an error message, well technically a blank screen - the symbol just went away....