Some digital pregnancy tests display a symbol resembling a book, often referred to as an hourglass or loading symbol. This indicator typically appears while the test is processing the urine sample to determine the presence of human chorionic gonadotropin (hCG), a hormone produced during pregnancy. The appearance of this symbol signals that the test is underway and the user should wait for the final result.
This visual cue serves as a waiting indicator, preventing premature interpretation of the test result. By displaying a book-like image, the test clearly communicates that the assessment is in progress. Historically, pregnancy tests relied solely on color changes to indicate a positive or negative result, which could lead to misinterpretations. The inclusion of a processing symbol adds a layer of clarity and reduces ambiguity.