Von Willebrand disease (VWD) is the most common inherited bleeding disorder, affecting up to 1% of the general population. It occurs when a protein called von Willebrand factor, which helps blood clot properly, is either missing, too low, or doesn’t work the way it should. The condition affects men and women equally, though women often experience more noticeable symptoms because of menstrual bleeding and childbirth.
How Von Willebrand Factor Works
When you cut yourself or damage a blood vessel, your body needs to quickly form a plug to stop the bleeding. Von Willebrand factor (VWF) is the protein that makes the first step possible. It binds to the damaged vessel wall and then acts like molecular glue, grabbing passing platelets from fast-flowing blood and holding them in place. Without enough functional VWF, platelets can’t stick to the injury site effectively, and bleeding takes longer to stop.
VWF also has a second critical job: it carries and protects clotting factor VIII in the bloodstream. Factor VIII is essential for building a stable blood clot. When VWF is deficient or defective, factor VIII levels often drop too, compounding the bleeding problem.
Types of VWD
VWD is classified into six types based on whether the problem is the amount of VWF your body makes or how well it functions.
Type 1
Type 1 is the mildest and most common form. Your body produces VWF that works normally but doesn’t make enough of it. VWF levels below about 30% of normal are generally associated with a genetic mutation in the VWF gene, while levels between 30% and 50% may represent “low VWF” as a risk factor for bleeding rather than true VWD. Symptoms are often mild enough to go unnoticed until a surgery or dental procedure triggers unusual bleeding.
Type 2
Type 2 VWD means your body makes VWF, but the protein doesn’t function correctly. There are four subtypes:
- Type 2A: The most adhesive, effective forms of VWF are missing. VWF levels in the blood may look adequate on a basic test, but the protein can’t do its job properly.
- Type 2B: The VWF is actually too sticky. It binds to platelets prematurely while still circulating in the bloodstream, which uses up both the best-functioning VWF and platelets before they’re needed at an injury site.
- Type 2M: The VWF doesn’t bind well to platelets or vessel walls, but through a different mechanism than 2A. It’s a catch-all category for binding defects that don’t fit the other subtypes.
- Type 2N: The VWF can’t properly carry and protect factor VIII. This type looks a lot like hemophilia A on initial blood tests because factor VIII levels are very low, and distinguishing the two requires specialized testing.
Type 3
Type 3 is the rarest and most severe form. The body produces little to no VWF at all. People with type 3 VWD can experience serious spontaneous bleeding, including bleeding into joints and the gastrointestinal tract, similar to what’s seen in severe hemophilia.
Inheritance Patterns
Type 1 and most type 2 forms follow an autosomal dominant pattern, meaning you only need to inherit one altered copy of the VWF gene (from one parent) to have the condition. If one of your parents has it, you have roughly a 50% chance of inheriting it.
Type 3 and type 2N follow an autosomal recessive pattern, requiring altered copies from both parents. In these cases, both parents are typically carriers who may have no symptoms or very mild bleeding themselves. Because VWD is carried on a non-sex chromosome, it passes equally to sons and daughters.
Common Symptoms
The hallmark symptoms of VWD involve bleeding that’s harder to stop or heavier than expected. This doesn’t usually mean dramatic, life-threatening hemorrhages. For most people with type 1 or type 2, the signs are subtler and easy to dismiss as normal variation.
Nosebleeds are one of the most recognizable signs. In VWD, nosebleeds tend to start without any injury, happen five or more times a year, last longer than 10 minutes, and sometimes require medical intervention like nasal packing or cauterization to stop. Bruising is another common symptom: bruises that appear with little or no trauma, show up one to four times a month, are larger than a quarter, and feel raised rather than flat.
After a skin cut, bleeding that continues for more than five minutes is a red flag. Dental procedures can be particularly revealing. Oozing that lasts more than three hours after oral surgery, or a surgical site that requires packing to control, often prompts the first investigation into a bleeding disorder.
The Diagnostic Delay, Especially for Women
Despite being common, VWD is significantly underdiagnosed. A CDC survey found that women with VWD waited an average of 16 years between the onset of bleeding symptoms and receiving a diagnosis. Women reported experiencing an average of six distinct bleeding symptoms before anyone identified the underlying cause. While 76% of boys with VWD were diagnosed by age 10, half of girls weren’t diagnosed until after age 12, likely because heavy menstrual bleeding is so often normalized.
Diagnosis involves blood tests that measure how much VWF is in the blood (VWF antigen), how well it functions (VWF activity), and factor VIII levels. Under the 2021 guidelines issued jointly by the American Society of Hematology and other international organizations, a VWF level below 30% of normal confirms type 1 VWD regardless of symptoms. For people who do have abnormal bleeding, a level below 50% is sufficient for diagnosis. Further specialized testing determines the specific type.
Treatment Options
Treatment depends on the type and severity of VWD and what’s triggering the need for intervention, whether that’s a planned surgery, a bleeding episode, or ongoing prevention.
The first-line treatment for many people is desmopressin, a synthetic hormone that signals the body to release its stored VWF and factor VIII into the bloodstream. It’s given as a nasal spray or injection, is inexpensive, and has a strong safety record. Desmopressin works well for most people with type 1 VWD and some with type 2, particularly for covering minor surgeries and dental procedures. In type 2A, however, the drug can raise VWF levels without actually improving function, which limits its usefulness. In type 2N, the boost in factor VIII it provides wears off quickly.
When desmopressin isn’t effective or appropriate, replacement therapy with concentrates that contain VWF (sometimes combined with factor VIII) is the next step. These are either derived from donated plasma or produced synthetically. People with type 3 VWD, who produce virtually no VWF, typically rely on these concentrates. Some with severe type 3 or serious type 1 VWD benefit from a regular, ongoing schedule of preventive infusions rather than treating bleeding only after it starts, particularly if they experience joint bleeding or gastrointestinal bleeds.
Tranexamic acid, a medication that helps stabilize clots once they form, is commonly used alongside other treatments or on its own for mild bleeding. It’s especially useful for dental procedures and nosebleeds.
Managing Heavy Periods
Heavy menstrual bleeding is one of the most common and disruptive symptoms for women with VWD. Multiple approaches can help, often used in combination. In a study at a tertiary care center, the hormonal intrauterine device (the 52-mg levonorgestrel IUS) had the highest satisfaction rate at 66%, controlling bleeding more effectively than other single treatments. Combined oral contraceptives were the most commonly used first treatment, controlling bleeding in about 36% of women when used alone but performing better when paired with tranexamic acid. Tranexamic acid alone controlled bleeding in about 23% of women, though it was frequently combined with other therapies. Extended-cycle oral contraceptives, which reduce the number of periods per year, were another effective strategy.
Surgery and Dental Work
If you have VWD and need surgery, your care team will plan ahead to make sure your clotting factors are at safe levels. Current guidelines recommend targeting both VWF activity and factor VIII levels at 50% of normal or higher for at least three days after major surgery. For women with VWD who want an epidural during labor, VWF activity levels between 50% and 150% of normal are the recommended target range. These levels are typically achieved with desmopressin or factor concentrates given before and after the procedure.
Even routine dental cleanings can require preparation. If you’ve been diagnosed with VWD, letting your dentist and any surgeon know ahead of time allows them to coordinate with a hematologist and have the right treatments on hand, which makes the procedures themselves straightforward and safe.