One line on an EPT pregnancy test means that the woman is not pregnant or the test was inconclusive. This conclusion depends on where the line is located.
EPT pregnancy tests have two windows where lines should appear, a square control window and a round results window. According to the directions included with EPT pregnancy tests, a line should appear in the control window to indicate that the test has worked properly. One line in the round window means that the woman is not pregnant or that there is not yet enough pregnancy hormone to be detected. Two lines in the round window form a positive symbol and indicate she is pregnant. WebMD reports that home pregnancy tests are approximately 97 percent accurate, especially if taken a week after a missed period.