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From DES to Makena and More: The Dangers of Endocrine Disruptors

Research on the hormonal drug DES and similar pharmaceuticals suggests that these chemicals can cause birth defects and cancers, not only in those exposed, but also in their children and even their children’s children. Dr. Barbara Cohn of PHI’s Child Health and Development Studies comments on their research showing generational effects from hormone-altering drugs and chemicals.

  • MedShadow
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Fifty years ago, a study showed that a drug called diethylstilbestrol (DES) given to pregnant mothers to reduce preterm births, instead raised the risk of a rare vaginal cancer in their daughters to 40 times that of the general population. Since then, scientists have discovered that these so-called DES daughters, sons, grandchildren and the DES mothers are also more likely to experience malformed reproductive organs, breast cancer and a slew of reproductive problems.

Now, a new study from PHI’s Child Health and Development Studies (CHDS) program shows that the children of women who were prescribed the drug Makena during pregnancy, intended to prevent pre-term birth, had higher rates of cancer than those who were not exposed to the drug in utero. The research also reveals that children, now ages 18 to 58, born to the 181 mothers in the study who had been prescribed the drug, were twice as likely to have any cancer diagnosis, four times as likely to have had prostate cancer and five times as likely to have had colon or rectal cancers.

Since that first DES study in 1971, scientists have identified more than 1,000 similar endocrine-disrupting chemicals (EDCs) in our plastics, cosmetics and even foods. It can be difficult to isolate the effects of these everyday exposures on our bodies, but the research on DES, Makena and similar drugs suggests that these chemicals can cause myriad birth defects and cancers, not only in those exposed, but also in their children and even their children’s children.

The new CHDS study may just be the start of our understanding of the harms that Makena may have caused. As the women age, more effects may become clear, just as they did with DES.

Dr. Barbara Cohn, director of CHDS, explains that she and her researchers were inspired to look at Makena’s impacts because the rate of colon cancer in people under 50 has doubled over the past 30  years. However, even the fivefold increase in risk of colon cancer they found among those exposed to Makena in utero can’t explain all 18,000 cases that experts estimate will be diagnosed this year. There must be other factors at play, one of which may be endocrine disruptors seeping into our everyday lives.

Barbara Cohn
Doctors believed that they were helping people (with the drug). It was true that this clinical trial in the fifties suggested it didn’t do much. But clinical trials were new in the 1950s, and we also have on the other side, patients who are desperate to have babies, who want help. It’s a formula for potential disaster.

Dr. Barbara Cohn, director Child Health and Development Studies

While DES and Makena were designed to have biological effects on our bodies, many EDCs came about by accident. Most were never intended to be consumed, but now they find their way into our bodies as pesticides on food, BPA in our water bottles and  even absorbed through our skin in lotions and cosmetics.

One well-known endocrine disruptor is dichlorodiphenyltrichloroethane (DDT)—the now-banned pesticide. Cohn and her team published a study in April 2021 that showed that the grandchildren of women who’d been exposed to DDT went through puberty at a younger age and were more likely to develop obesity than those who weren’t exposed. The team has been following women who had DDT in their blood during and shortly after pregnancy for decades. A previous CHDS study showed that the women and their daughters were both at higher risk for breast cancer than women who were not exposed to the chemical. Since the granddaughters in the current study were a median age of 26, it’ll probably be another couple decades before we know if, like their mothers and grandmothers, they’re at higher risk for breast cancer.

Click below to read the full story in MedShadow.

Originally published by MedShadow

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