Sex-Based Bias in Medicine

Women represent just under half of the population globally and just over half of the population in the United States. Despite this relatively equal presence, research and development into women’s health conditions are still critically underfunded, and women are impacted by gender inequity in healthcare on a daily basis.

Key Highlights

Women represent just under half of the population globally and just over half of the population in the United States. Despite this relatively equal presence, research and development into women’s health conditions are still critically underfunded, and women are impacted by gender inequity in healthcare on a daily basis.

PRA Health Sciences
PRA Health Sciences

When discussing health equity, it’s important to remember that biological sex is different from gender. Regardless of gender presentation, people who are assigned female at birth are at higher risk for certain conditions, autoimmune diseases, cardiovascular diseases, chronic pain, and depression.

Despite this, women’s health research is severely lacking, not only in terms of equitable inclusion in research studies, but in terms of funding for research into female-specific diseases as well. For example, an estimated one in 10 women are affected by endometriosis during their reproductive years, but a normalization of painful symptoms of menstruation, a lack of awareness from both the public and physicians, and a lack of interest in researching female-specific diseases means that there is still no known cure for the condition. In late 2020, the US Senate approved a historic amendment to double federal funding for endometriosis research, bringing the National Institutes of Health (NIH) allocation up to a total of $26 million—out of a budget of $42.9 billion in 2021.

Identifying Research Gaps

Organizations like the Society for Women’s Health Research (SWHR)—a US-based nonprofit focused on improving women’s health through science, policy, and education—are working to combat sex-based disparities in health equity. In addition to identifying research gaps and addressing unmet needs in women’s health spaces, SWHR works to improve public policy and increase public awareness of women’s health issues.

Perhaps one of the most important accomplishments the SWHR has achieved, though, is creating seismic change in the clinical research paradigm. In 1977, an edict from the US Food and Drug Administration (FDA) banned most women “of childbearing potential” from participating in Phase I and early Phase II clinical research studies. The exclusion was broad, and included any premenopausal woman who was capable of being pregnant, regardless of her relationship status, whether or not she used contraception, or if her husband was vasectomized. While these policies stemmed from a desire to protect vulnerable populations—that is, unborn children—and were largely influenced by the discovery of the relationship between drugs like thalidomide and diethylstilbestrol (DES), they failed to consider the long-term effects on women’s health.

Because women were now excluded from early-stage clinical trials, the medical community experienced a dearth of data on how drugs affect women. With the formation of the first Department of Human Services task force on women’s health in 1983, policymakers began to realize that many factors—including body size, body fat distribution, and hormones, among other sex-related biological responses—influence how drugs are metabolized in women’s bodies. But even with this shift in public understanding, drug-specific clinical trials were still routinely conducted in all-male cohorts until 1988.

Women in Clinical Research

In 1993, the FDA published new guidance rescinding the 1977 guideline excluding women from early clinical research. The new guidelines acknowledged that the previous edition “restricted the early accumulation of information about response to drugs in women that we could utilize in designing Phase II and III trials, and has perhaps delayed appreciation of gender-related variation in drug effects,” and acknowledged that this exclusion “may have perpetuated, in a subtle way, a view of the male as the primary focus of medicine and drug development.”

Conditions like anxiety and depression, for example, are twice as common in women compared with men, and roughly one in six women in the US takes an antidepressant medication. Despite this, there is a significant lack of gender-specific research on the pharmacokinetics and pharmacodynamics of antidepressant drugs, which data suggest are metabolized differently between the sexes. The research that does exist is conflicting, and is further confused by biological differences in pre- and post-menopausal women. On the other hand, attention-deficit/hyperactivity disorder (ADHD) is critically underdiagnosed in young girls and women; research remains focused on young boys, and women are frequently not diagnosed until they reach adulthood. And although the percentage of women who filled a prescription for medication to treat ADHD increased by 350% between 2003 and 2015, particularly among women in their 20s and 30s, research is still primarily focused on the potential negative effects of stimulant medication on fetal safety—not on things like how hormones can impact the efficacy of these treatments or the possible cardiovascular side effects associated with central nervous system stimulants.

Race, Ethnicity, and Women’s Health

Thanks to the efforts of the SWHR and a 2016 NIH policy declaring sex a key biological variable for preclinical research and mandating that all NIH-funded research “must either include both female and male research subjects or explain why they do not,” researchers have begun working to correct sex-based research inequalities. But despite these wins for women’s health, much of the damage has already been done.

Women’s reproductive health topics in particular still suffer from these previous inequalities. In addition to endometriosis, gaps persist in knowledge about birth control, fertility, menopause, and other aspects of sexual and reproductive health. For women of color, these gaps in reproductive health knowledge are even more significant: data show that people of color are still routinely left behind by clinical research.

Black women of reproductive age, in particular, are living with the unintended consequences of inequity and discrimination in health research. According to the Commonwealth Fund, the US is one of only two countries that reported an increase in maternal mortality since 2000. For Black women, the maternal death rate is 37.1 per 100,000 pregnancies, and Black women with a college degree have a 60% higher risk of maternal death than their White and Hispanic counterparts.

Learn more about how decentralized clinical trials can bridge the diversity gap

Black people are also more likely to experience hypertension than any other ethnic group. Preeclampsia—the dangerous elevation of a pregnant woman’s blood pressure after the twentieth week of pregnancy—is responsible for 6.4 fatalities per 10,000 pregnancies. Black women are 60% more likely to experience the condition. But despite efforts to balance clinical research cohorts by sex, cardiology clinical trials are skewed to include more men than women. Because reproductive research remains underfunded, the etiology of preeclampsia remains largely unknown, and Black women continue to pay for decades of clinical research inequality with their lives.

Equity Begins in the Boardroom

The reality of the women’s health landscape illustrates two things. First, prioritizing women isn’t enough—race- and ethnicity-based considerations must be made in order to truly create a reality in which men’s and women’s health issues are treated with the same level of care and concern. Second, the first steps toward equity in health research begin with pharmaceutical companies themselves.

While some biopharmaceutical companies have doubled down on their women’s health efforts, others have chosen to disband their women’s health units. Although these investments may have changed the lives of women living with endometriosis or polycystic ovary syndrome, the lack of fatality associated with these conditions means that Research & Development (R&D) interest is generally limited.

Another factor limiting the R&D interest in women’s health conditions is the gender imbalance found in many pharmaceutical board rooms. Management diversity by gender in the industry decreased from 2014 to 2016. As of 2017, most companies still fell short of the global benchmark of 30% representation for women in the C-suite. Without women in key decision-making roles, it’s no surprise that women’s health issues are either deprioritized or not advocated for in the first place.

PRA Health Sciences strives to amplify the diverse voices of women in the healthcare and pharmaceutical industries. To celebrate this year’s International Women’s Day, the organization held numerous events focused on amplifying women’s voices, including those who are a part of Women of Color in Pharma (WOCIP). PRA’s Arts and Crafts for Relaxation Club also partnered with Knitted Knockers, a charity that makes gentle prosthetics for women in post-mastectomy care. PRA is a proud member of WOCIP, a member of the Proud Science Alliance, and supporter of women in science, technology, engineering and math (STEM).

PRA’s internal commitment to equality is reflected across each of its centers of expertise. For each disease state that PRA works in, the PRA team is committed to elevating equality and ensuring a future in which women, regardless of race or ethnicity, receive the equitable healthcare they deserve.

Learn more about our commitment to diversity, equality, and inclusion

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