The inheritance of both Type 1 and Type 2 VWD occurs in a dominant pattern. They can have VWD because they inherited the gene from either parent who has the same changed gene or they could have a new change in the VWD gene which has occurred for the first time in the family. Someone with Type 1 of Type 2 VWD has a 50-50 chance to pass on the changed gene to each child.
Type 3 is the least common type of VWD and is caused by having both changed genes. This is a recessive inheritance pattern. Recessive means that a person much inherit two changed copies of the gene in order to have Type 3 VWD. If both parents have mild VWD and have a child together there is a 25% chance that the child will inherit both changed genes (one from each parent) and have Type 3 VWD.