Explanation

Von Willebrand disease (VWD) is a problem with bleeding that you get from your parents, and both boys and girls can get it. Normally, when you bleed, a protein called von Willebrand factor helps your platelets stick together to form a clot.

But, if you have VWD, you either have low levels of this protein or it doesn't work properly, so bleeding can be heavy and hard to stop.