People with the genetic disorder von Willebrand Disease have a defective or missing protein that plays a vital role in blood-clotting. In men and women with the disease, small blood cells can’t properly stick together or attach themselves to blood vessel walls.

This can lead to uncontrolled bleeding after injury, dental procedures, or surgery. People with the disease also experience frequent nosebleeds and bruise easily. Women suffer abnormally heavy bleeding during menstruation and after childbirth.

Most patients have the mildest of the three main forms of the disease, Type 1, in which there are low levels of the protein that helps the blood clot. As treatment, doctors often prescribe desmopressin, which stimulates the release of the protein.

Patients with Type 2 von Willebrand disease have normal levels of the protein but it doesn’t work properly, and patients with Type 3 don’t produce the protein at all. In these cases, doctors prescribe replacement therapy, which is purified from human plasma.

The disease affects men and women equally but women are more likely to be diagnosed because of problems with menstruation. Still, says hematologist Dr. Michelle Sholzberg from St. Michael’s hospital in Toronto, many people aren’t even aware they have the disease and suffer silently with excessive bleeding and resultant iron deficiency anemia.

“Getting a proper diagnosis can be empowering for patients, particularly women who have been suffering from heavy periods without knowing why. Ultimately,” she says, “the goal is to make people feel safe and strong.”