Many home pregnancy
tests claim to be 99 percent accurate on the day you miss your period. Although research suggests that some home pregnancy tests
don't consistently spot pregnancy this early, home pregnancy tests are considered reliable when used according to package instructions one week after a missed period. Fertility
drugs or other medications that contain HCG
might interfere with home pregnancy test results. However, most medications, including antibiotics and birth control pills, don't affect the accuracy of home pregnancy tests.
Although rare, it's possible to get a positive result from a home pregnancy test when you're not actually pregnant. This is known as a false-positive.
A false-positive might happen if you had a pregnancy loss soon after the fertilized egg attached to your uterine lining (biochemical pregnancy) or you take a pregnancy test too soon after taking a fertility drug that contains HCG. An ectopic pregnancy or menopause
also might contribute to misleading test results.
so if you have got continuous negative results on 40 and 50 days after last intercourse, then it can be safely deemed that there s no pregnancy.regards