One in three women will experience heavy periods, also known as heavy menstrual bleeding (HMB).

HMB can be painful and distressing, and lead to poor mental and physical health. Over time, some women may develop anaemia, which can, in serious cases, require a blood transfusion.

Heavy periods: underlying causes and diagnosis

For some women, HMB will be the result of an imbalance of three main factors within the inner womb lining: inflammation, issue oxygen levels and blood clotting. These are called ‘non-structural’ causes. For others, heavy periods are caused by another condition, such adenomyosis or fibroids. These are ‘structural’ causes and require a referral to a gynaecologist for professional support and treatment.

Identifying HMB can take time because it can be difficult for women to distinguish if their menstrual bleeding is heavy or not. This can be exacerbated by societal pressure not to discuss periods, which means women may not always come forward for medical help immediately.

Women may need a hospital referral for tests and investigations to confirm if the underlying cause of their HMB is structural. This inevitably means diagnosis takes longer and treatment is subsequently delayed.

Dr Marianne Watters is being funded by Wellbeing of Women to research differences in menstrual fluid from women with heavy and normal menstrual blood loss. This is a crucial first step towards development of a non-invasive test that could be carried out by GPs to confirm heavy periods and identify underlying structural causes.  The key aim is to streamline the diagnostic process and enable women to get appropriate support and treatment at an earlier stage.

Can menstrual fluid confirm heavy periods?

We already know that women with heavy periods have different levels of inflammation, oxygen and blood clotting markers in their womb lining compared with women with ‘normal’ periods (where blood loss is less than 80ml). However, invasive biopsies are needed to examine this at present.

By comparison, menstrual fluid, which typically includes blood, cells from the womb lining and mucus, can be easily collected by women themselves using a menstrual cup.

Dr Watters and her team, which will comprise researchers from the Centre for Reproductive Health at the University of Edinburgh, will:

• study samples of this fluid from women with heavy and normal periods to determine if markers linked to HMB can be detected in menstrual fluid, e.g. protein levels, colour or pH
• compare menstrual fluid from women with and without fibroids and adenomyosis to see if underlying structural causes can be identified.

Dr Watters, Clinical Research Fellow at the Centre for Reproductive Health at the University of Edinburgh and a junior doctor specialising in obstetrics and gynaecology, says:

“Heavy menstrual bleeding is a common issue but rarely spoken about. Societal stigma that exists around the issue of periods means lots of women may be unsure if their periods are heavy, may feel embarrassed or think that their level of blood loss is normal, or have their concerns dismissed. These factors can combine and lead to a delay in getting the help they may need.

“Heavy periods can have a major impact on personal and professional relationships and a woman’s own emotional wellbeing and physical health. Without any treatment or support, there is also the risk of developing anaemia which affects almost three in ten women globally.

”I hope to find out if menstrual fluid can be used as a reliable method to identify heavy periods and possible causes like adenomyosis or fibroids that may need further care by a gynaecologist. This research is necessary to inform the development of a simple test that could be carried out either at home or a clinical setting. This could be transformational in developing precision medicine within women’s health."

The study is expected to last for three years and will involve studying fluid samples from 40 women with measured menstrual blood loss. Each person taking part in the research will undergo an ultrasound to determine if they have fibroids, adenomyosis or neither and will then be asked to donate a sample of menstrual fluid from their period for this research.

Previous research funded by Wellbeing of Women includes studies to better understand the causes of heavy, irregular periods and how we can treat them in women with fibroids and adenomyosis.

Our health information on periods and menstrual health

As a women’s health charity, part of what we do is improve awareness and understanding of women's reproductive and gynaecological health.