My son has someting called von willebrands disease, it is a blood disorder.
Apparently it is quite common and doesn't usually cause any problems.
We only discovered it because he started to bruise very easily and had nose bleeds.
It is like a very mild form of haemophillia, you bruise easily and in females it causes extremly heavy periods.
It often goes undiscovered and is believed to be a common cause for hysterectomies being carried out needlessly, or so my sons blood specialist tells me.
It may be worth reading up about, theres loads of info on the net about it.
Good luck
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