Female participants have traditionally been removed from toxicology or biomedical studies for many reasons. While progress has been made since 1993, when the National Institutes of Health mandated the inclusion of women and minorities in any health research sponsored by the government, there is still a long way to go.
The science that informs medicine, including disease prevention, diagnosis, and treatment, regularly fails to take into account the critical influence of gender and sex. This occurs in the early stages of study where, in the published findings, women are omitted from animal and human studies, or the sex of the animals is not specified.
Once clinical trials start, researchers often do not register sufficient numbers of women or fail to evaluate or disclose data separately by sex when they do. This hinders our ability to describe major differences that might improve everyone’s wellbeing.
The number one killer of women is cardiovascular disease, and it affects men and women differently at all stages. But, according to the study, only one-third of cardiovascular clinical trial participants are female and only 31 percent of cardiovascular clinical trials involving females report findings by sex.
Significant endocrine changes, including puberty, pregnancy, and menopause, have been specifically related to an increased risk of depression during a woman’s life. Women metabolize drugs differently from men. But less than 45 percent of animal studies on clinical depression use female laboratory animals.
Finally, in young, non-smoking females, lung cancer, which kills more women every year than breast, ovarian, and uterine cancers together, is remarkably prevalent, and researchers have found that female hormones, particularly estrogen, affect the development and mortality of lung cancer. Having more women in research studies has led to evidence that some therapies for lung cancer perform better for women than for men.
Even if women are included in toxicology research, whether those researches are adequately broad-ranging is not clear. For instance, although studies assess mammary tumors for chemical exposure, they do not research the effect of chemicals on the production of mammary glands. This may be important considering that teenaged girls use more grooming items than adult women.
Some change has been brought by government policies requiring the representation of women and minorities. They also contributed, for example, to the development of women’s health services at various government departments, leading to several significant breakthroughs, including much of the knowledge available about how cardiovascular disease impacts women differently from men, and the various risks of hormone replacement.
However, these policies are not always strictly followed, even in government agencies with stringent and clear policies around women, such as the National Institutes of Health, the Food and Drug Administration, and the Centers for Disease Control.