Scientists Call for Women’s Inclusion in Research

By Lenah Bosibori

Nairobi, Kenya: When a patient walks into a hospital and receives medicine, they expect it to have been properly tested and proven safe and effective. But health experts warn this is not always true for women.

Women can respond differently to medications because of differences in hormones, body composition, metabolism, and other biological factors. Yet for years, medical research has treated the male body as the standard for developing and testing medications. Experts now want this to change.

Speaking during a Media Science Café on gender-responsive research and development organized by IQVIA and the Drugs for Neglected Diseases initiative (DNDi), researchers, regulators, and bioethicists called for women to be included more meaningfully in health research, from the design of studies to clinical trials, to the monitoring of medicines after they reach the market.

Historically, clinical drug trials relied on a standard male body, typically a 70-kilogram man as the default benchmark for human biology, assuming treatments would work the same way in women. 

Following the thalidomide tragedy in the mid-20th century, which caused severe birth defects, global regulators barred women of childbearing age from early trials to avoid pregnancy risks. In addition, researchers frequently avoided including women due to fluctuating hormonal cycles, which were seen as complicating study results. 

Consequently, most modern medicines were developed, dosed, and approved with little data on female biology.

At the media café, the researchers agreed that simply having women in a clinical trial is not enough, but they must also consider the real-life barriers that keep women from participating, as well as the biological differences that may affect how medicines work in their bodies.

Dr. Caroline Kithinji, Head of Training at the Science and Ethics Review Unit at the Kenya Medical Research Institute (KEMRI), said research teams often overlook the responsibilities women carry outside the clinic.

“When researchers review studies, they often require women to be on ‘acceptable contraception,’ yet that requirement is rarely imposed on men,” she said.

She added that researchers should ask why women miss appointments instead of simply blaming them for failing to follow study schedules. “A woman may be caring for children, travelling a long distance to the clinic, or losing a day’s income by attending an appointment,” Kithinji said. “If we want women to participate, we have to understand their day-to-day realities.”

Dr. Dearie Okwu, a clinical trial physician and Therapeutic Work Program Lead at DNDi, shared an example of a mother who wanted to join a trial that required time at a hospital.

“She asked who would take care of her family while she was away,” Okwu said. The research team eventually found a way to accommodate her children so she could take part. She said this shows why clinical trials should be built around people’s real lives, not rigid schedules.

Experts said the problem begins even before participants are recruited. Kithinji said communities should be involved from the earliest stages of research, including when study ideas and proposals are being developed.

“Early engagement can help researchers understand the concerns of women and other groups who may otherwise be left out,” she said. “Why are we left out?” she asked, arguing that researchers should always identify who is missing from a study and why.

She also called for ethics committees and regulators to be involved earlier in the research process, which could help catch design flaws before proposals reach the approval stage. Experts suggested that reviewers follow clear guidelines when assessing gender responsiveness, asking questions such as: Who is missing from the research? Why are they missing? Who holds power in the research process? And who will eventually use the findings?

Looking Beyond the Male Body

Gender-responsive research also means examining biological differences between men and women. Dr. Moses Alobo, Director at the Science for Africa Foundation, said researchers should consider using more female animals during the early stages of drug development.

He noted that scientists have long relied heavily on male animal models, leaving gaps in understanding how medicines affect females. “Is it possible to actually start using female animal models?” he asked, adding that researchers could record the stage of the reproductive cycle when female animals receive medicines, to see whether hormonal changes influence how a drug works.

Similar questions arise when medicines are tested in women. Researchers may need to account for hormonal changes and menstrual cycles when studying certain medicines. Though this can make trials more complex and costly, experts said these factors should not be ignored.

The issue becomes even more important in pregnancy. Regulators pay close attention to teratogenicity, the possibility that a medicine could cause abnormal development in an embryo or fetus. Experts said more research is needed to understand how medicines affect women during pregnancy and other stages of life.

Testing a medicine in a clinical trial is only part of the process. Dr. Christabel Khaemba, Deputy Director of Product Safety at Kenya’s Pharmacy and Poisons Board (KPPB), said regulators are increasingly focused on how medicines perform once approved and used by the wider public.

This is where post-marketing surveillance comes in. Once a medicine is on the market, healthcare workers, pharmaceutical companies, and researchers can report suspected side effects and other safety concerns. Such monitoring can uncover problems that never surfaced during clinical trials, which typically involve far fewer participants than the millions of people who eventually use a medicine.

Experts noted that social media can also offer early signals of possible side effects, though such reports must be investigated and weighed against reliable scientific evidence before any conclusions are drawn.

Women Can Be Included Safely

Experts stressed that including women, even pregnant women, does not mean ignoring safety. Research in Kenya, including studies on women in HIV pre-exposure prophylaxis and pregnant women in RSV vaccine trials, shows that women can be included when the right safeguards are in place.

The real challenge, they said, is striking the right balance between protecting women and ensuring medical evidence reflects their experiences. Historically, concerns about protecting women of reproductive age from harm led to their widespread exclusion from clinical studies. While safety must remain a priority, experts warned that excluding women creates a different risk: medicines developed without enough evidence of how they actually affect women.

Gender gaps in health research go beyond clinical trials. Experts called for more funding opportunities for women and women-led ventures, including dedicated competitions and grants. They also urged research institutions to reconsider how they treat career gaps, particularly those linked to women’s family and caregiving responsibilities.

Building a more inclusive research system, they said, requires changes across funding, recruitment, study design, community engagement, regulation, and monitoring.

The experts agreed the question should no longer be whether women can be included in research, but whether studies are designed in ways that make their participation possible and meaningful.

For patients, the issue goes beyond representation; it is about whether the medicines they take were tested with people like them in mind. As health research becomes more gender-responsive, experts say women should no longer be treated as an afterthought. Their biological differences, experiences, and needs must be considered from the start so the medicines developed are safe and effective for everyone who ultimately uses them.