A month ago I took a home pregnancy test and it came back positive. I went to the doctor for a scan and he coudn't see anything; blood samples were taken and came back positive. The doctor said i must come after the 18th of June maybe he will see something on the scan then, I didn't go because by that time I was having my periods. The periods continued for 2 and 1/2 weeks and they were very heavy ( that was abnormal for me and I thought i was miscarrying). I've just taken a pregnancy test and it's still positive. I've got a doctors appointment for Monday the 9th of July.So I want to know how long does it take for a pregnancy test to be negative after miscarriage.