Prop. 65’s Assault on Women

Prop. 65’s Assault on Women

ere in the “advanced” state of California, Proposition 65, aka the Safe Drinking Water and Toxic Enforcement Act of 1986, appeared as a ballot initiative in the fall of that year—and a fall it was … especially for women. Its authors intended it to protect California citizens and the state’s drinking water from chemicals known to cause cancer, birth defects, or other reproductive harm (and to inform citizens about exposures to such chemicals), but many of Prop. 65’s unintended consequences have turned the voters’ expectations to nightmares. As one pundit put it, Prop. 65 is like Frankenstein’s monster, running amok across the countryside and harming practically everyone but lawyers.

Prop. 65 spawned not just entirely new classes of perpetrators, but also entirely new classes of victims. In at least one special case, amazingly, perpetrator and victim are the same—a class of citizens known as women (more on that later). Women are victimized because Prop. 65 includes a list of “chemicals known to the state to cause cancer or reproductive toxicity,” and on that list is a substance known as progesterone. This is not the synthetic, ersatz progesterone known as methyprogesterone acetate, but the bioidentical hormone, the same one that women (and men as well) produce in their bodies! It’s a natural molecule.

For various reasons, women do not always produce enough progesterone, so for the past 20 years, many women have been supplementing with it to alleviate the symptoms of menopause and PMS. Many swear by it. What they have not known, however, is that in 1988, progesterone was placed on the Prop. 65 “hit list” owing to someone’s analysis of the then current literature. This analysis ( did not find any carcinogenicity of progesterone in animals or women. In rats, however, there were some changes in mating behavior, especially in males, and some fetal deaths in late-pregnant females. Yet this study was conducted back in the 1970s, when it wasn’t widely appreciated that progesterone could be used for birth control or even as a potential abortifacient. Interestingly, when progesterone levels are not high enough, miscarriage can occur. Balance is everything.

In women, there were no statistically confirmed associations or pregnancy outcomes, but there was one case study that confirmed female virilization (development of masculine characteristics) for several progestogens—but not for progesterone. Progestogens (also referred to as progestins) are hormones that produce effects similar to those of progesterone, the only natural progestogen (all the others are synthetic).

Fast-forward to 2005: the kind of lawyers who are usually either chasing ambulances or looking for a good class-action suit discover the presence of progesterone on Prop. 65’s list. The supplement market hasn’t been the same since. Not only have progesterone manufacturers been forced to wear Prop. 65’s standard skull-and-crossbones statement—“This product contains ingredients known to the state of California to cause cancer, birth defects, or other reproductive harm” (which isn’t even true), but they have also been subject to draconian fines and damages that have made it impossible to continue to offer progesterone to all but the largest firms.* And, given the FDA’s penchant for “kicking them when they’re down,” the permissible explanations for what progesterone can be used for and what it can do have all but disappeared.

Regarding the role of women as both perpetrators and victims, pregnant women naturally produce much higher levels of progesterone (up to five times normal), which makes them highly impervious to disease. But according to the twisted logic of Prop. 65, they could be forced to wear the skull-and-crossbones statement during pregnancy, along with listing the progesterone-provoking fetus as an accomplice!

*A new summary of reproductive information (based on the same literature as before) was published with the intent of having a public meeting in 2004 to establish “recognized safe levels of progesterone usage” ( Unfortuately, the level of proof required to remove something from the Prop. 65 list is so much higher than that required to put it on the list that the appeal failed.

FREE Subscription

  • You're just getting started! We have published thousands of scientific health articles. Stay updated and maintain your health.

    It's free to your e-mail inbox and you can unsubscribe at any time.
    Loading Indicator