There are TONS of little hormonal problems than can cause periods not to arise, not to mention athletes that are in training that rigorous often do not cycle.

So for example:

> Late developer that enters in to rigorous training at a young age. Not timed to start cycling until already in heavy training. Period does not manifest

> Chronic Ovarian cysts
> Under/over active hormone production (of any sort. females DO produce testosterone, just in smaller amounts.)


Particularly if she grew up with sub-standard health care, there is NO logical reason for her to immediately think "jee, i haven't cycled, i must be a hermaphrodite."