Trends in the prevalence of menstrual disorders 2011-2020: a descriptive study of patients presenting to primary care in England

Date of Approval: 
2021-05-24 00:00:00
Lay Summary: 
Many women and girls suffer from problems connected to menstruation. Such problems include physical symptoms such as heavy blood loss and pain, but also problems with mood and mental health. Some may find it difficult to function as usual in their home, social and work/educational environments. While in some women and girls menstrual problems may be mild, for others they can be debilitating. In some cases, there is a clear underlying explanation for the problem such as a bleeding disorder, endometriosis or cancer. In many cases, no clear cause for such menstrual disorders is discovered. Previous studies have suggested that 22-40% of women in the UK who menstruate have a menstrual disorder and that 3-8% consult their GP about heavy menstrual bleeding each year. However, there is a lot of uncertainty in these estimates and even less is known about how common menstrual disorders are in adolescent girls, or about how patterns of menstrual disorders are changing. It is important to know how common menstrual disorders are and whether the number of women and girls seeking help from their GP is changing over time in order to help plan health services and examine where there may be unmet need. This study will aim to evaluate this, at the same time investigating whether patients in different age, ethnic, regional and socio-economic groups access services equally.
Technical Summary: 
This descriptive epidemiology study will aim to describe trends in the prevalence of menstrual disorders (dysmenorrhoea and heavy menstrual bleeding) in women and girls aged 10-60 in the past decade (2011-2020) in England. The population of interest will be defined as any patient who has had a primary care consultation resulting in a SNOMED code suggesting heavy menstrual bleeding or painful menstrual bleeding (but not other forms of abnormal uterine bleeding such as unpredictable bleeding, post-coital bleeding or amenorrhoea). Patients will be eligible for inclusion regardless of eventual diagnosis/management choice or lack thereof, as the motivation to seek medical care for a menstrual disorder will be considered equivalent to a menstrual disorder: this is in line with NICE guidelines which suggest taking the patient-centred approach of accepting a patient’s opinion that their menstrual bleeding is excessive rather than necessarily seeking to quantify it (Lethaby et al. 2019; NICE 2018b). Time trend analysis and regression models will be used to calculate prevalence of menstrual disorder each year from 2011 to 2020, both overall and in subgroup analyses, which will be performed by age, ethnicity, region and patient-level deprivation. The data obtained from CPRD will be linked to IMD (Index of Multiple Deprivation) 2015 data to determine patient-level deprivation.
Health Outcomes to be Measured: 
- Prevalence of menstrual disorder annually from 2011 to 2020, defined using SNOMED medical codes encompassing heavy menstrual bleeding and dysmenorrhoea; - Prevalence of menstrual disorder stratified by age group, deprivation (patient-level Index of Multiple Deprivation), region and ethnicity. We are aware of the limitations regarding self reported ethnicity, and its high proportion of missingness, and will be mindful to consider and report these when we present results stratified by ethnicity.
Application Number: 

Kate Fleming - Chief Investigator - University of Liverpool
Jaime Bolzern - Corresponding Applicant - University of Liverpool
Anna Head - Collaborator - University of Liverpool
Pieta Schofield - Collaborator - University of Liverpool

Patient Level Index of Multiple Deprivation