1. Women with hemophilia are often undiagnosed or misdiagnosed
Historically hemophilia was thought of as a “man’s disease,” and for many years the belief was that women in families with hemophilia could only be carriers of the disease, meaning they could pass the affected gene on to their children. But we now know that some women who carry the hemophilia gene have low enough levels of factors VIII or IX that they also have hemophilia, and that women with hemophilia will often experience similar symptoms and complications as men with hemophilia. Nevertheless, a lack of awareness on the part of primary care doctors means that many women with hemophilia today still go undiagnosed or misdiagnosed.
2. Women are more likely to have mild hemophilia
According to a 2021 study of nearly 30,000 people conducted by researchers at the Centers for Disease Control and Prevention, nearly one-fifth of patients with mild hemophilia admitted to treatment centers in the US are female. The percentage of women and girls with severe or moderate hemophilia is thought to be somewhere in the range of less than 0.5% to a little more than 1%.
A much more common bleeding disorder in women is von Willebrand disease, which affects more than 3 million Americans—about 1 percent of the population, or approximately 1 in every 100 people. This inherited bleeding disorder occurs equally in men and women.
3. One of the most common signs of hemophilia in women is heavy menstrual bleeding
Heavy menstrual periods are defined as:
- Bleeding for more than seven days, from the time it began until it stopped
- Flooding or gushing of blood
- Passing clots that are bigger than a quarter
- Changing a tampon and/or pad every two hours or less on the heaviest day
Other common signs and symptoms of hemophilia in women include:
- Being told you are “low in iron” or have anemia
- Heavy bleeding from dental surgery, other surgery or childbirth
- Frequent nosebleeds that last longer than 10 minutes
- Bleeding from cuts lasting longer than five minutes
- Easy bruising (weekly, raised and larger than a quarter)
4. Making the diagnosis can be complicated
There’s no one simple diagnostic test to confirm that a woman has hemophilia or another type of bleeding disorder, so providers often have to piece together various symptoms, multiple lab results and timing of the lab testing to confirm the diagnosis. One of the challenges for providers is to determine whether heavy periods are related to normal variation or a sign of an underlying bleeding disorder.
To help women prepare for diagnostic tests and understand their results, the National Hemophilia Foundation (NHF), in cooperation with the CDC, produced a brochure called “What Women and Girls Should Know About Getting Tested for Bleeding Symptoms: Your Guide to Lab Tests, Screening Tools and Health Exams.”
5. Pregnant women with hemophilia require special care
Pregnant women with hemophilia are at an increased risk for serious bleeding after delivery because the high levels of factor during pregnancy can fall back to lower levels after delivery. That’s why most women with a bleeding disorder need treatment with clotting factor or another treatment to prevent excessive bleeding at the time of delivery. All pregnant women with hemophilia should be cared for by a maternal-fetal medicine physician, which is a doctor who specializes in high-risk pregnancy.
6. There are specialized centers for women and girls with bleeding disorders
Women and girls with hemophilia can seek care at one of the approximately 141 hemophilia treatment centers (HTCs) across the country, a nationwide network of centers established in the 1970s to diagnose and treat hemophilia and other bleeding disorders. But many HTCs have established special designated clinics to diagnose and treat women and girls with bleeding disorders. To locate a center near you, consult this map created by the Foundation for Women & Girls with Blood Disorders.