What happened to the pregnancy test bar?

At present, the widely used early pregnancy diagnostic test paper is very convenient and fast to apply, so many pregnant women or pregnant women will prepare early pregnancy diagnostic test paper at home to judge early pregnancy. The specific operation steps are to take female urine, especially morning urine will be more accurate. Insert the end marked with MAX of the early pregnancy diagnostic test paper with reagent into urine. The urine level must not exceed this line. Results can be observed after 1-5 minutes, if ten minutes later the results will be invalid. For the judgment of the result is only in the white display area at the top of a red line is negative, this time a bar means that there is no pregnancy, and in the white display area will appear two different shades of red line, it is positive, in this case it is suggested that the possibility of pregnancy is relatively large, but this situation has no way to judge whether intrauterine pregnancy or ectopic pregnancy, or need to go further to the hospital for examination, and a clear diagnosis.