Welcome to healthcaremagic forum,
First i would like to ask you to get the metformin
removed though it may not be the cause of the present situation , consult back your gynecologist for the same.
do present with irregular cycles often mistaken to pregnancy
but not that pregnancy is impossible, but better way to confirm or rule it out as the urine test turned less informative is by a Blood HCG
Its sensitive than the urine test.
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