On average, women in the UK live longer than men, yet the UK stands out as the country with the largest female health gap in the G20 and the 12th largest globally, with women spending three more years in ill health and disability when compared to men.

The health of the 51%: women report in 2014 identified the widening disparities for girls and women during their adolescent, reproductive and post-reproductive years. Many of the issues raised over ten years ago remain relevant today. Despite women representing more than half of the global population and therefore accounting for a significant proportion of the patient population, most health and physiology research has excluded female participants, with research data collected predominately from men, and subsequently generalised to women. This has led to critical gaps in our understanding about women-specific conditions, such as menopause, endometriosis and fibroids. In addition, little is known about how general conditions that affect both men and women (e.g. dementia, cardiovascular disease, mental health) impact the sexes differently, as specific data analyses are often missing.

Why is this?

The exclusion of women from clinical trials stems from the thalidomide tragedy. Thalidomide was a widely used drug in the late 1950s and early 1960s for the treatment of nausea in pregnancy. However, thalidomide use resulted in severe birth defects in thousands of children. This led to the Food and Drug Administration issuing guidelines in 1977, banning pregnant women from participating in phase I/II clinical trials. Although the ban was lifted in 1993, it meant women were excluded from such trials for decades. Other postulated reasons for preferring males in research include concerns that physiological changes associated with the menstrual cycle make females a more complex group to study; researcher bias from predominantly male researchers; through to assumptions that the Caucasian male body is the default “norm”. Historically, there is also evidence that some groups of women have been less likely to be included as research participants, such as such as women from ethnic minorities, women with disabilities, and lesbian and bisexual women.

Does it matter?

Representation and participation of women in medical research is important because males and females are physiologically and genetically different. Conducting health and physiology research in males exclusively disregards these differences. Given the gender health gap and focus of androcentricity (the practice of perceiving the world through a masculine viewpoint), medical research has historically led to disadvantages for female patients, and critical gaps in our understanding of how particular treatments and drug regimes impact women. This increases the risk of adverse effects and limits the effectiveness of medical interventions tailored to their needs. For example, research found that 76 out of 86 commonly used drugs exhibit sex-based pharmacokinetic differences (PDF). Yet dosing guidelines often fail to account for this, leading to females experiencing adverse drug reactions at nearly twice the rate of men.

Equally, women may be missing out on vital support, often impacting their mental health and education or employment opportunities. Research examining the discourse surrounding patients with endometriosis found that the pain and experiences of these patients were often dismissed as psychological. Such attitudes, alongside the lack of open discussions surrounding women’s health and menstruation, means that it now takes women an average of 8 years 10 months between their first GP visit and getting a diagnosis. This is despite endometriosis affecting 1 in 10 women and people assigned female at birth.

How can we narrow the existing gender data gap in medical research?

Currently, only 2% of the overall public research funding is dedicated to reproductive health and childbirth. Furthermore, this percentage has not shifted in the past decade. One of the benefits of medical research is that it informs the development of clinical guidelines. These then provide recommendations intended to optimise patient care by promoting interventions of proved benefit and discouraging ineffective or potentially harmful interventions. Therefore, if there are sex differences in symptom presentation and / or clinical responses to treatment options, it is essential these are acknowledged. 

The Women’s Health Strategy in England, highlighted the limited research into women’s health issues such as endometriosis and Polycystic Ovarian syndrome (PCOS), which affect millions of women. This strategy’s six-point plan for change emphasised the need to address the lack of evidence into women’s health conditions, improve the representation of women of all demographics in research, and tackle the data gap by ensuring existing data is broken down by sex. Going forward, as nurse researchers, we need to rethink how we design our studies to ensure we capture more robust and inclusive data and consider practical approaches which can overcome challenges to participation, i.e. for women with caring responsibilities, or those with access issues.  Our research must place women’s voices and priorities at the heart of the study and prioritise the unique needs of women across all backgrounds. By investing in research that reflects the diversity of real-life experiences, hopefully treatments can be developed that will make a real difference to women’s outcomes.