As COVID-19 vaccines started to become available, a number of people— knowing my science background— reached out to me for my take on the new vaccines. One friend was concerned about rumors she had heard that women were excluded from vaccine trials because they could be harmful to female reproductive organs. All I could tell her was that if she had concerns about a vaccine or drug because it was never tested on fertile women, then she had reason to be concerned about almost every drug and treatment on the market. Yes, the unfortunate reality is that most medications aren’t adequately tested on women, especially women who aren’t on birth control.
Wait, are women not allowed in research trials?
Historically, women, especially women of reproductive age, were excluded from medical research in general. In 1993 the National Institutes of Health (NIH) repealed an earlier Food and Drug Administration (FDA) ban on research of reproductive-age women, but no federal oversight mechanism was put in place. So while the letter of the law changed, that was about it. Even though reproductive-age women are now allowed in medical research, they are still less likely to be studied or to be enrolled 50/50 with men. Consider that even though cardiovascular disease is the #1 killer of both men and women, the majority of research into drugs and protocols has been done only or largely on men [1].
When women nowadays are enrolled in studies, normally cycling (read: potentially fertile), pregnant, and/or breastfeeding women are still regularly excluded. Furthermore, premenopausal women are typically required to be on hormonal birth control for the duration of the study.
There are multiple rationales for why women are excluded from research trial, but two big reasons are ethics and money. Both arguments are insufficient to justify the exclusion of women from most research studies.
Argument #1 for why women are excluded from research studies: Studying pregnant women isn’t ethical
The ethical argument against involving women who are pregnant, could-become-pregnant, or breastfeeding, is that the study then not only involves the woman, but also her developing (or newborn) baby. Medications (including dosages) that are safe for adults are not necessarily safe for preborn or born babies, and could therefore cause developmental harm. It makes sense then that pregnant women should be excluded from studies that might harm their children, especially if prior cellular and animal trials have indicated that this might be a possibility.
Reality Check: Pregnant women deserve good data on whether medicines and treatments are safe
The fact of the matter is that pregnant and breastfeeding women still have to make decisions about the food, vaccines, and medication they take during pregnancy. Conditions that require medication before pregnancy do not disappear after a baby is conceived, and conditions that arise during pregnancy may also require treatment.
This means that many treatments are still being tested on pregnant women, but instead of taking place in a clinical setting with careful observation and help readily available, these drugs are tested in the “real world” by women. Any data collected can only be done by surveys or reporting after-the-fact. This makes it especially difficult to improve our understanding of important questions like “will this medication cross the placental barrier?” or “how does the body respond differently to this treatment while pregnant?”
If a treatment has passed through cell and animal trials without any red flags, and the potential benefits outweigh the potential risks, women could reasonably participate in clinical trials. This could not only make a difference in their own health, but the health of future women.
Argument #2 for why women are excluded from research trials: Studying women, especially naturally cycling women, costs more than studying men
At first glance, it may appear that medical researchers simply operate under the assumption that women are the same as men… but with breasts. And, undoubtedly, researchers today are influenced by the “publish or perish” culture in science. Investigators have to find ways to cut costs and time from studies or risk a similar study beating them to publication.
Dr. Sarah Hill, evolutionary biologist and author of This is Your Brain on Birth Control, has explained how conducting a trial with naturally cycling women can cost three times as much as a study with men (or women on birth control, whose cycles and normal hormonal fluctuations have been flatlined). Factors like recruitment (since so many women are on the pill), scheduling (to have women come in at a specific point in their cycle in order to control for different cycle phases), and assembling a research team (who now need to come in on various days of the month to accommodate the different women in the study) all add to the expense and logistical difficulty of studying naturally cycling women.
Reality check: The end does justify the means, even if the means cost more
While a woman’s cycle makes her “expensive” to study, her cycle is also crucial to her health. Likewise, because a woman’s cycle impacts so many organ systems, it also impacts different diseases, and how medications will work within her body. Without studying fertile women, however, we cannot draw conclusions about how this happens and in what ways. Each woman becomes her own walking science experiment, with a “sample size” of 1.
Case in point, women are twice as likely to have an adverse reaction to a drug than men, but the reasons behind these reactions have yet to become a topic of research. And because research on women is expensive, diseases that primarily affect women (such as anxiety, autoimmune diseases, depression, IBS, migraines, thyroid disease, and female-specific cancers) are considered less-desirable areas of research and are therefore less likely to see new treatment options in the first place. And because there are biological differences between premenopausal and postmenopausal women, stratified research across the female lifespan is necessary.
The bottom line
Contrary to current research practices, the world is not divided into “normal people” and women. Women deserve better than having to fend for themselves in finding treatments and making medical decisions. They deserve updated research requirements that ensure that they, their cycles, and the medical conditions that most affect them are included in the study processes that lead to scientific advancements. Women, be they naturally cycling, pregnant, or breastfeeding, shouldn’t be excluded from research trials.
References:
[1] Keteepe-Arachi T, Sharma S. Cardiovascular Disease in Women: Understanding Symptoms and Risk Factors. Eur Cardiol. 2017 Aug;12(1):10-13. doi: 10.15420/ecr.2016:32:1. PMID: 30416543; PMCID: PMC6206467.Additional Reading:
Your hormones during a natural cycle vs. your hormones on the Pill
