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CLEARBLUE TESTS, is this true ?

Fa • Thu, Aug 04

I thought others might be interested to learn how the Clear Blue digital with conception indicator works. In the picture below, you see the display screen. This reads either 'not pregnant', '1-2 weeks pregnant', '2-3 weeks pregnant' or '3+ weeks pregnant'. This indicates weeks since conception based on urinary HCG concentration. The middle picture shows the inside of the test. The two test strips both detect HCG. The top strip is a high-sensitivity HCG test (I think 25MIU). It is this strip that triggers the test to say either pregnant or not pregnant. The bottom strip has a control line (to the left) and a low-sensitivity HCG test (possibly 50MIU or 100MIU?). It is the difference between those two lines that triggers the test to display the weeks since conception. Finally, the strips at the bottom are three examples of the low sensitivity stip taken from 3 different tests. The bottom one produced a result 1-2 weeks, the middle one 2-3 weeks and the top one 3+ weeks.