There are many mysteries in medicine. One of the mysteries that has plagued me for years may now have a solution.
When I was in medical school I learned about Stein-Leventhal syndrome. Women with this condition tend to be overweight and have excess body hair. Their ovaries have lots of little cysts, and don’t seem to function normally because the women have irregular periods, or no bleeding at all. Although this may seem to be just an annoyance, it is really more serious. Lack of periods may lead to endometrial cancer. Often the best treatment for this syndrome is oral contraception, because the hormones help regulate periods and reduce the risk of developing this cancer. However, often the reason a woman with this syndrome will seek medical care is because of infertility, and The Pill won’t help with that!
Through the years the name changed to “sclero-cystic ovary syndrome” and now it goes by “Poly-Cystic Ovary Syndrome” (PCOS). I used to think that the cause of PCOS was obesity; indeed, some women who are obese will have symptoms similar to women with PCOS, but their ovaries are normal. In the past experts said that PCOS was caused by an increase in the level of Luteinizing Hormone. LH is made by the pituitary gland; this hormone helps control ovarian function. Usually it spikes before ovulation, but people with PCOS have relatively constant, high levels. What causes the LH to be elevated? No one seemed to know. This seemed to be more of a finding than a solution to the mystery.
Now there appears to be a solution to the mystery of PCOS’s cause, and I should have guessed it years ago. I first became interested in endocrine disrupting chemicals when I had a chance discussion with a professor of chemistry over 20 years ago. These chemicals are everywhere, and in essentially every person’s body who has been tested. The latest ones to grab media attention are the omnipresent “forever chemicals”, PFAS. They have been found in drinking water supplies all over the USA in miniscule amounts. You might be thankful that they are not more concentrated, but the reality is that many endocrine disruptors are more troublesome when very dilute. A tiny pinch of an endocrine disruptor in an Olympic-sized swimming pool can be enough to cause serious problems!
Many modern chemicals are endocrine disruptors—they interfere with our hormonal systems. Bisphenyl A (BPA) is added to plastics to make them flexible; it was one of the first chemicals to be recognized as harmful. Perhaps you have a water bottle that claims it is “BPA free”. Don’t celebrate too much, because the chemicals that replace BPA, such as BPF, are often equally harmful.
More than 90% of people in the USA carry BPA in our bodies, and women with PCOS have higher levels of BPA than women without PCOS. This strongly suggests that BPA causes some cases of PCOS. As a result of this endocrine disruption, many also have increased levels of male hormones, and thus their increased body hair.
As bad as BPA and other endocrine disruptors are on adults, their effect on a developing fetus may be both worse and more insidious. Fetal exposure to BPA may be associated with several problems affecting both females and males—but it is too early to know with certainty.
My goal is for people to be able to have control over their own fertility. Dangerous chemicals such as BPA may reduce fertility involuntarily. I look forward to more testing of chemicals that may affect endocrine systems, and better regulation should they be found dangerous.
©Richard Grossman MD, 2024