A new Canadian-based study has found that women who take a certain type of fertility drug may be at risk for developing the human form of mad cow disease.

Apparently — and this was news to me — there are certain types of fertility drugs that are derived from urine, specifically the urine of older women. It sounds like the stuff of witch doctors, but it's true. The urine has been purified and combined with other goodies to make fertility drugs called gonadotropins that are used to stimulate a woman's ovaries to produce multiple eggs per cycle, instead of just one.

Human urine contains proteins called prion proteins that are found naturally in the human body. Under normal conditions, these proteins are harmless. But when they mutate, they can clump together in the brain and cause degenerative brain disorders such as Creutzfeldt-Jakob disease, or CJD — the human form of mad cow disease. CJD attacks the brain, destroying its delicate cells and tissue and eventually leading to death.

The research team behind this latest study tested dozens of samples of urine-derived fertility drugs. All were contaminated with prion proteins.

Now, before you panic, you should know that so far, the risk of developing CJD after taking urine-based fertility drugs is theoretical. There have never been any documented cases of the disease linked to these drugs, so researchers don't know that it could happen. But after completing this study, they do know that they need to look into this.  

Dr. Neil Cashman, scientific director of PrioNet Canada and the study's co-principal author, said in a press release, "There has never been a single recognized case of Creutzfeldt-Jakob disease in a woman who received these urinary pharmaceuticals," he stressed. "So that's a good thing. It means it's not common, if there is transmission. ... So if there's a risk, it's an extremely small one."

Can fertility drugs cause mad cow disease?
New study finds that fertility drugs used by thousands of women each year may increase the risk of Creutzfeldt-Jakob disease.