Scientists Avoid Using Female Rats in Research Due to Hormone Fluctuations
The gender bias in medicine is nothing new – but did you know that researchers specifically avoid using female lab rats for fear that their hormones will interfere with the study!?
Consider this – researchers who are studying a new thyroid medication, heart drug, sleeping pill or anti-depressant , use male rats. Why? To avoid the hormonal fluctuations of the female rats.
Wow…that sounds like the dark ages, but in fact, it is happening today. It wasn’t that long ago that the National Institutes of Health (NIH) established guidelines to include women and minorities in clinical research with the NIH Revitalization Act of 1993.
“Yet even when researchers study diseases that are more prevalent in women — anxiety, depression, thyroid disease and multiple sclerosis among them — they often rely on male animals.” Dr. Zucker
The NIH recently announced that researchers have to start using female rats – which will come into play starting in October. This New York Times article sums it up pretty nicely. Here are some highlights:
“Contrary to the conventional wisdom in laboratories, there is far more variability among males than among females on a number of traits and behaviors, Dr. Zucker has found. Yet even when researchers study diseases that are more prevalent in women — anxiety, depression, thyroid disease and multiple sclerosis among them — they often rely on male animals, according to another analysis led by Dr. Zucker, who has written extensively on gender bias in scientific research.”
Considering that thyroid disease affects women 8x more often than men, and that thyroid itself is a hormone that has an immediate and direct affect on our sex hormones, its alarming to think that the female cycle not be considered! I know my thyroid and my estrogen are definitely in an intimate relationship. And yet knowing that, researchers don’t want to use female rats to study thyroid because of the interference – the cost and complexity goes up when researchers have to control for the hormonal fluctuation.
The good news, however, is that change is on the way – it’s about time!