Haemophilia in women and girls

Women and girls can have haemophilia; although many experience diagnostic delays or may remain undiagnosed.^1–3

Heavy menstrual bleeding is the most common symptom experienced.^2,3If you experience menstrual issues, frequent bruising or prolonged bleeding, it’s important to talk to your healthcare provider.⁴

How haemophilia is diagnosed

Haemophilia A is caused by genetic changes in clotting factor VIII (FVIII) and haemophilia B is caused by genetic changes in clotting factor IX (FIX).^1,5 These clotting factors are essential for the formation of blood clots, which stop bleeding.¹ Diagnosis relies on both measuring the level of clotting factor in your blood to assess how your blood clots, and genetic testing to confirm if you have a change to FVIII/FIX in your genome.¹

Symptoms overview

Some women and girls might have similar symptoms to men (e.g., bruising, bleeding in joints and serious or prolonged bleeding after minor injuries or procedures), but may also experience:^1,3

Heavy, prolonged menstruation^1,3
Excessive and/or prolonged bleeding during ovulation²
Iron deficiency as a result of excessive blood loss^1,3
Increased endometriosis risk¹
Increased risk of haemorrhagic ovarian cysts¹
Excessive and/or prolonged bleeding during childbirth²
Excessive and/or prolonged bleeding during miscarriage or pregnancy termination²
Excessive and/or prolonged bleeding during perimenopause^1,2

A person and person on a beach

Severity of haemophilia

The severity of haemophilia depends on the clotting factor levels (FVIII for haemophilia A, FIX for haemophilia B) in your blood. Women and girls with haemophilia can fall into any of the following severity categories.^1,6

Severe haemophilia: factor level of <1% of normal
Moderate haemophilia: factor level between 1–5% of normal
Mild haemophilia: factor level between >5–<40% of normal

Some women and girls can also be carriers of haemophilia (meaning they have one copy of FVIII/FIX with genetic changes), have factor levels of ≥40% (in the normal range), but experience different levels of bleeding.^3,6

Symptomatic carriers: women who have normal factor levels and still experience bleeding⁶
Asymptomatic carriers: women who have normal factor levels and do not experience bleeding⁶

Haemophilia inheritance

In haemophilia, genetic changes in FVIII/FIX may occur spontaneously or can be inherited from your parents.^1,3

In your genome, genes are packaged into 23 pairs of chromosomes.¹ This includes sex chromosomes (X and Y), which are involved in determining your sex.¹

Men have an X and a Y chromosome¹
Women have two X chromosomes¹
The information for clotting factors VIII and IX is on the X chromosome¹

Since men have only one copy of the information for FVIII/FIX in their genome (one X chromosome from their mother), if they have genetic changes in FVIII/FIX they will have haemophilia.¹ Women have two copies of the information for FVIII/FIX in their genome; two X chromosomes with one provided from each parent.¹ A woman can develop haemophilia if she inherits:

One copy of FVIII/FIX with genetic changes from either parent – resulting in:
- Haemophilia (factor levels of <40%), or
- Being a carrier with or without symptoms of haemophilia^1,3,6
Two copies of FVIII/FIX with genetic changes from both parents– resulting in:
- Haemophilia (factor levels of <40%)^1,3,6

If a woman with haemophilia or a carrier has children with a man who does not have haemophilia, each child has a 50% chance of inheriting FVIII/FIX with genetic changes. Daughters may have haemophilia or be carriers, and sons may have haemophilia.¹

For a woman with haemophilia or who is a carrier of haemophilia (having one copy of FVIII/FIX with genetic changes), and a man with haemophilia, there is:

A 100% chance of a daughter being affected
- 50% chance of a daughter having or being a carrier of haemophilia (one copy of FVIII/FIX with genetic changes)
- 50% chance of a daughter having haemophilia (two copies of FVIII/FIX with genetic changes)
A 50% chance of a son having haemophilia^3,7

Experiencing haemophilia at different life stages

Childhood and adolescence

Girls need the same specialised care as boys, including regular visits to a haemophilia treatment centre.⁵ Early haemophilia diagnosis and treatment are key, as well as planning for the changes associated with adolescence.^2,8

Your multidisciplinary haemophilia care team, which can include a gynaecologist, can provide information on possible symptoms specific to women and girls, including those relating to menstruation, and treatment options, and also assist with any gynaecological discussions, as required.²

Girls may experience heavier bleeding when they begin to menstruate.^1,2 Your healthcare team can explain what to expect during a first period, what might be unusual and when to seek assistance.²

As heavy bleeding during menstruation can lead to iron deficiency/anaemia, your healthcare provider can check the iron levels in your blood regularly and this can be treated appropriately.²

Heavy menstruation and discomfort may also affect quality of life and mental and emotional wellbeing with possible feelings of embarrassment or concerns about self-image. A mental health specialist within your healthcare team can provide support and counselling to help navigate these feelings.^1–3,5

Family planning

Haemophilia is a genetic condition, which means it is inherited and runs in families.¹ When you’re thinking about starting a family, preconceptual counselling, including genetic counselling, can provide you with information about:

The risk of haemophilia being inherited
The options around conception, including pre-implantation diagnosis and prenatal diagnosis
The risks to both mother and child during pregnancy and birth, and the steps taken to reduce these
How haemophilia in a newborn is managed^1,2

Conception options can include conceiving naturally or fertility treatment, such as in-vitro fertilisation (IVF).¹

IVF can allow screening of early embryos to identify those that contain FVIII/FIX with genetic changes.^1,2 Egg retrieval and related procedures require planning to take into account any bleeding risk.²

If you have conceived naturally and would like to know if your baby might have haemophilia, prenatal diagnosis can help find out. Please consult with your health care team for further information.

Pregnancy and childbirth

Pregnancy brings unique challenges for women with, and carriers of haemophilia, as it can affect both the mother and the baby, making specialist care and monitoring essential.^1,5 A multidisciplinary healthcare care team, including specialists from the haemophilia treatment centre and an obstetrician, should be involved.¹

They can:

Monitor iron deficiency during pregnancy, and treat as appropriate²
Monitor clotting factor levels to see if treatment is needed during childbirth^1,2
Help you in preparing a birth plan covering the care of both you and the child during and after birth, which can be shared with the healthcare team; this is crucial to ensure a well-planned delivery^1,2
Following birth, provide information on what is expected for normal bleeding for you, the signs of excessive bleeding and when to seek assistance^2,4

Perimenopause and menopause

Your healthcare team can provide information on the changes to menstruation during perimenopause, as there may be a greater risk of excessive or prolonged bleeding, and any other relevant menopause-related symptoms.^1,2Hormone therapy may be considered for treatment of heavy menstrual bleeding.²

Ageing

Women with haemophilia can have similar joint bleeding as men,⁵ and clinical and silent bleeds in joints can lead to progressive joint damage over time.^1,8,9 Monitoring of bleeds and early treatment is important to prevent long-term joint damage.^5,8 As you get older you may also experience osteoporosis and factures.^1,10

For health conditions related to ageing, additional treatment may be required.⁵ It is important to discuss any other treatments you may need to take with your healthcare team, as these may include treatments that affect blot clotting, such as aspirin.^5,8,11

To find out more about the topic you can also visit this website: Women and girls with hemophilia - eLearning Platform

References:

World Federation of Hemophilia. Women and Girls with Hemophilia. Available at: https://elearning.wfh.org/resource/women-and-girls-with-hemophilia/ (accessed September 2025).
van Galen K, Lavin M, Skouw-Rasmussen N, Fischer K, Noone D, Pollard D, et al. Haemophilia. 2021;27:837–7.
The European Haemophilia Consortium. Is haemophilia (fe)male? Available at: EHC-Booklet-on-Women-with-Haemophilia-and-Female-Carriers.pdf (accessed September 2025).
The Haemophilia Society. Women living with bleeding disorders. Available at: https://haemophilia.org.uk/resources/publications/booklets/women-living-with-bleeding-disorders/ (accessed September 2025).
Srivastava A, Santagostino E, Dougall A, Kitchen S, Sutherland M, Pipe SW, et al. Haemophilia. 2020;26(Suppl. 6):1–158.
van Galen KPM, d’Oiron R, James P, Abdul-Kadir R, Kouides PA, Kulkarni R, et al. J Thromb Haemost. 2021;19:1883–7.
HemAware. Understanding hemophilia inheritance. Available at: https://hemaware.org/bleeding-disorders-z/understanding-hemophilia-inheritance (accessed September 2025).
The Haemophilia Society. Understanding haemophilia. Available at: https://haemophilia.org.uk/resources/publications/booklets/understanding-haemophilia-2/ (accessed September 2025).
Gualtierotti R, Solimeno LP, Peyvandi F. J Thromb Haemost. 2021;19:2112–21.
The Haemophilia Society. Ageing with a bleeding disorder: Managing trips, falls and mobility. Available at: https://haemophilia.org.uk/resources/publications/booklets/ageing-with-a-bleeding-disorder-managing-trips-falls-and-mobility/ (accessed September 2025).
Mannucci PM, Schutgens REG, Santagostino E, Mauser-Bunschoten EP. Blood. 2009;114:5256–63.