What if the test is negative after the 5 minute reaction time, but becomes positive after an hour?
Do not attempt to interpret results after the five minute test reaction time. Depending on the concentration of hCG in the test specimen, positive results may be observed in as little as 40 seconds. However, to confirm negative results, the complete reaction time of 5 minutes is required. A positive result can only be determined within this time interval. A percentage of “false positive” pregnancy tests can be attributed to misinterpretation of results due to a failure to follow test instructions with precision. Here, you should not rely on any positive result that does not show up within the time limit stated in the test instructions. All pregnancy test brands have the possibility of displaying an evaporation line.
