It happens I took my time studying the topic recently. So basically you're saying that doctor, professional gynecologist, do not take blood sample for HCG but use something less reliable? Blood test give us result in numbers, there's meaning to that numbers (for example, less than 5 - definitely not pregnant) and that is the first thing every gynecologist in Russia will advise the patient to do if patient says that she's late but test comes without second string. Or quite the opposite, two strings with normal monthlies. And, of course, if victim of the test is still not convinced (there can be still pregnancy or extrauterine pregnancy, which can give strange result for HCG) there's always sonogram of uterus (but if she wants to do it for free there's a queue 2 months long for this). I don't know what gynecologysts do in your country but I suppose it's not something different. And that was the reason for my question, test can be wrong but medical procedures gives you precise result. And yeah, irregular birth control pills (why is she not using Novaring?) with serious stress (modeling contest, for example) can cause amenorrhea, and in that state pregnancy is impossible.
