Bleeding Disorders in Women and Girls: State of the Science and CDC Collaborative Programs

Women and girls with bleeding disorders experience abnormal and excessive bleeding that can negatively impact their overall health and quality of life. Improved public and provider awareness and understanding of the unique needs of women and girls with bleeding disorders is needed to achieve appropriate care and treatment and to ensure the best possible health outcomes and quality of life.

Group of women standing together

About This Summary

The Centers for Disease Control and Prevention (CDC) recently published a review article in the Journal of Women’s Health that provides an overview of the state of the science of bleeding disorders in women, and describes CDC activities related to

  1. public health monitoring of bleeding disorders in women;
  2. scientific review and collaboration to inform healthcare gaps in identifying and caring for women with bleeding disorders; and
  3. development of health promotion and education programs to bring awareness about bleeding disorders to both women in the population at large and various healthcare providers who care for women.

This information will be used to guide the development of new public health programs aimed at improving diagnostic and healthcare services for women with bleeding disorders. Also, it helps women with bleeding disorders navigate a complex healthcare system and find the specialty care services they need. Below is a summary of the key points from the review article.

Bleeding Disorders in Women

A person’s blood contains small cells called platelets and proteins called clotting factors. When bleeding occurs, the platelets and clotting factors undergo a series of steps to form a clot at the site of injury, and thus, stop the bleeding.  Bleeding disorders can occur because of a problem at any step in this clotting process.

Inherited bleeding disorders affect up to 1% of women and girls in the United States (US). While they affect both men and women, bleeding disorders create unique problems for women and girls because of the impact they can have on their reproductive health. A girl’s first period is typically the first major bleeding event she faces. It is estimated that one in five girls and women experience heavy menstrual bleeding and among those, about 1 in 4 have a bleeding disorder. During pregnancy and delivery, women with bleeding disorders are at increased risk of dying from bleeding complications. They also have a higher rate of bleeding after pregnancy (postpartum hemorrhage) than women without bleeding disorders and are at increased risk for other reproductive health disorders such as ovarian cysts and endometriosis.

Other bleeding symptoms (which occur in both men and women) include nose bleeds, gum bleeding, easy bruising, excessive bleeding after surgical or dental procedures, and in rare cases, bleeding into their joints or muscles, which can have long term impacts on their mobility (ability to move around and perform routine activities).

It is important that women with bleeding disorders be cared for at specialized treatment centers called hemophilia treatment centers (HTCs). Their healthcare providers should have expertise in both bleeding disorders (hematology) and obstetrics and gynecology (OB-GYN), including an understanding of how to treat heavy menstrual bleeding. Their care should also include genetic testing and counseling on their risk of passing down their specific bleeding disorder to their children. It is important that care during pregnancy is coordinated between their obstetrician and hematologist.

CDC Activities

Types of Bleeding Disorders

von Willebrand disease (VWD) – a lack of, or problem with, the functioning of von Willebrand factor (VWF), a protein that’s important in ensuring the platelets are able to function properly and that normal amounts of another important clotting factor (factor VIII (8)) are maintained in the blood.

Hemophilia – a lack of either clotting factor VIII (8) or clotting factor IX (9).

Rare clotting factor deficiencies – a lack of other clotting factors beyond factors VIII and IX (these are very rare because a person must inherit a gene from each of their parents to develop these disorders).

Platelet disorders – many different types of disorders that cause a lack of platelets (thrombocytopenia) or a problem with platelet functioning, or both.

Fibrinolytic disorders – a problem with the proteins needed to break down the clot once the bleeding has stopped; in these disorders the defect in the proteins leads to the clot breaking down too quickly, resulting in delayed bleeding.

Connective tissue disorders – excessive bleeding caused by fragile blood vessels, which makes it difficult for the platelets to begin the process of forming the clot at the site of injury.

Public Health Monitoring

Since 1998, CDC together with partners including the US Hemophilia Treatment Center Network (USHTCN) and the American Thrombosis and Hemostasis Network (ATHN) has supported ongoing health monitoring of people with diagnosed bleeding disorders who receive care at federally-supported HTCs across the US. This clinical network currently includes 145 HTCs.

The current health monitoring program is known as Community Counts. Through Community Counts, CDC annually collects basic information on the entire population of people with bleeding disorders who receive care at HTCs. Additionally, more in-depth information is collected from a subset of people who receive care at an HTC and agree to participate in the Community Counts Registry. Findings from Community Counts include the following:

  • Because one of the major disorders treated at HTCs is hemophilia and hemophilia affects more men than women (because the pattern of inheritance is sex-linked), the number of boys and men receiving treatment at HTCs has surpassed the number of girls and women. Nonetheless, between 2012 and 2020 the number of females being treated at HTCs increased 47%.
  • Across all years (2012 through 2020), over 28,000 women and girls received care for a bleeding disorder at an HTC. This represents over 40% of the total people who received care for a bleeding disorder during this time.
  • VWD was by far the most common disorder, accounting for over 60% of girls and women seen at HTCs for a bleeding disorder.
  • As of March 2021, nearly 4,000 women and girls have opted to participate in the Registry, which allows for more in-depth monitoring of treatment, complications, and outcomes over time. These women and girls comprise 14% of all females treated at HTCs for bleeding disorders.


Over the past few decades, CDC scientists have led or collaborated on many important studies related to the identification and healthcare needs of women with bleeding disorders. A summary of the findings from these research activities is as follows:

  • Several CDC studies in the early 2000s demonstrated that heavy menstrual bleeding is often a hallmark feature for women with bleeding disorders, particularly for VWD. For example, in their study of the experiences of US women with VWD, researchers documented that heavy menstrual bleeding was the most reported symptom1.
  • Not only has CDC research been essential to documenting the importance of screening women with heavy menstrual bleeding for bleeding disorders, a screening tool to help OB-GYNs and other primary care providers identify women with heavy menstrual bleeding was developed2,3 through CDC-sponsored studies.
  • Other CDC studies have demonstrated that women with bleeding disorders commonly experience lengthy delays from onset of bleeding symptoms to diagnosis. For example, one study4 documented on average a 16-year delay (range 0-39 years) between onset of abnormal bleeding symptoms and diagnosis. Another study5 reported that over 70% of adult women and 50% of adolescent girls who were eventually diagnosed with a bleeding disorder had experienced a delay from their initial bleeding symptoms to their diagnosis. The median delay was 10 years for adults and 4 years for adolescents.
  • CDC-sponsored surveys6,7 during the past two decades report significant gaps in many OB-GYNs’ understanding of the risks and impact of bleeding disorders in women. The most recent survey conducted in 20128 found that over half of OB-GYNs underestimated the prevalence of VWD in women and that many providers would not consider a VWD diagnosis among adult women with heavy menstrual bleeding.
  • CDC laboratory studies9,10 have provided evidence that lab testing used to diagnose bleeding disorders are often more difficult to interpret for women and girls because some test results may be altered by female hormones and the time during their menstrual cycle when their blood is drawn.

Non-CDC studies have provided context to the CDC findings that showed delayed identification of bleeding disorders in women and girls. Numerous studies have documented women’s reports of their barriers to care. In various studies, women reported that their symptoms made them feel isolated and stigmatized11,12,13 and that they have perceived discrimination and sometimes bullying from healthcare providers because of their gender, with their symptoms not taken seriously13. This can lead to women with heavy menstrual bleeding not seeking care and thus going undiagnosed and untreated14.

Health Promotion

The CDC currently funds and works closely with the National Hemophilia Foundation (NHF) and the Hemophilia Federation of America (HFA) to develop and carry out health promotion and prevention programs for women and girls with bleeding disorders. The desired outcomes for these programs are for

  • women and girls to recognize their bleeding symptoms and seek care;
  • healthcare providers to identify women and girls with signs and symptoms of a bleeding disorder and refer them to hematologists for diagnostic testing; and
  • hematologists to appropriately diagnose and provide treatment to women and girls to reduce bleeding disorder related complications.

The Better You Know campaign was developed by NHF and CDC to raise awareness of bleeding disorders among women and girls who may experience bleeding symptoms but have not yet been diagnosed and to increase knowledge and awareness among non-hematology healthcare providers. Better You Know includes various online and print materials.

The joint work between CDC and HFA includes activities to empower and educate women with bleeding disorders and women at risk for bleeding disorders. In 2019, discussion groups were held among adult women diagnosed with bleeding disorders to learn about their experiences with symptoms, diagnosis and treatment, and to identify perceived gaps in care.

Additionally, an online learning management module was developed to increase knowledge and awareness among undiagnosed and diagnosed females within the bleeding disorders community. The educational module provides information about self-advocacy, signs and symptoms of bleeding disorders, diagnostic testing and treatment, understanding life balance, and health promotion.

CDC’s future activities with NHF and HFA include working together to develop innovative provider training programs for hematologists and OB-GYNs.

Study Citation

Byams VR, Miller CH, Bethea FM, Abe K, Bean CJ, Schieve LA. Bleeding Disorders in Women and Girls: State of the Science and CDC Collaborative Programs. Journal of Women’s Health. 2022 March 11.


  1. Kirtava A, Drews C, Lally C, Dilley A, Evatt B. Medical, reproductive and psychosocial experiences of women diagnosed with von Willebrand’s disease receiving care in haemophilia treatment centres: A case-control study. Haemophilia 2003;9:292-297.
  2. Drews CD, Dilley AB, Lally C, Beckman MG, Evatt B. Screening questions to identify women with von Willebrand disease. J Am Med Women’s Assoc (1972) 2002;57:217-218.
  3. Philipp CS, Faiz A, Dowling NF, et al. Development of a screening tool for identifying women with menorrhagia for hemostatic evaluation. Am J Obstet Gynecol 2008;198:163.e1-e8.
  4. Kirtava A, Crudder S, Dilley A, Lally C, Evatt B. Trends in clinical management of women with von Willebrand disease: A survey of 75 women enrolled in haemophilia treatment centres in the United States. Haemophilia 2004;10:158-161.
  5. Srivaths LV, Zhang QC, Byams VR, et al. Differences in bleeding phenotype and provider interventions in postmenarchal adolescents when compared to adult women with bleeding disorders and heavy menstrual bleeding. Haemophilia 2018;24:63-69.
  6. Dilley A, Drews C, Miller C, et al. von Willebrand disease and other inherited bleeding disorders in women with diagnosed menorrhagia. Obstet Gynecol 2001;97:630-636.
  7. Dilley A, Drews C, Lally C, Austin H, Barnhart E, Evatt B. A survey of gynecologists concerning menorrhagia: Perceptions of bleeding disorders as a possible cause. J Womens Health Gend Based Med 2002;11:39-44.
  8. Byams VR, Anderson BL, Grant AM, Atrash H, Schulkin J. Evaluation of bleeding disorders in women with menorrhagia: A survey of obstetrician-gynecologists. Am J Obstet Gynecol 2012;207:269.e261-269.e265.
  9. Miller CH, Dilley A, Richardson L, Hooper WC, Evatt BL. Population differences in von Willebrand factor levels affect the diagnosis of von Willebrand disease in African-American women. Am J Hematol 2001;67:125-129.
  10. Miller CH, Dilley AB, Drews C, Richardson L, Evatt B. Changes in von Willebrand factor and factor VIII levels during the menstrual cycle. Thromb Haemost 2002;87:1082-1083.
  11. Khair K, Holland M, Pollard D. The experience of girls and young women with inherited bleeding disorders. Haemophilia 2013;19:e276-e281.
  12. Arya S, Wilton P, Page D, et al. “They don’t really take my bleeds seriously”: Barriers to care for women with inherited bleeding disorders. J Thromb Haemost 2021;19:1506-1514.
  13. Arya S, Wilton P, Page D, et al. “Everything was blood when it comes to me”: Understanding the lived experiences of women with inherited bleeding disorders. J Thromb Haemost 2020;18:3211-3221.
  14. Weyand AC, James PD. Sexism in the management of bleeding disorders. Res Pract Thromb Haemost 2021;5:51-54.