I suspect it's supposed to be very accurate.

You'd think that and it would be great if it were, but it turns out no. I haven't found a good fertility book/site/doctor yet who recommended I get one except for one doctor who said that some of them have bigger digital readouts for us glasses people. Of course, you don't have to read it right away, she smirked.

No, these baby pink wonders are designed to get the pregnancy-minded to part with an extra bunch of money.