Millions of women alive today were exposed to a chemical called DES – diethylstilbestrol – in their mother’s uterus. The chemical, an early synthetic estrogen, was administered to some pregnant women before 1971 to help reduce risk of miscarriages and prematurity.

Only later did doctors discover that it a) didn’t help with these complications and b) it heightened certain health risks to female babies exposed to the chemical.

My mother was given DES (though I only found out when I was in my 30s), so I’m one of those DES daughters and have reason to be interested in a new report in the New England Journal of Medicine that takes a thorough look at the heightened medical risks.

The scientists, from a slew of institutions including the National Institutes of Health, examined data from three studies started in the 1970s, encompassing 4,653 women exposed to DES as fetuses and 1,927 similar women who weren’t exposed. The amount of the chemical the women were exposed to varied from case to case; the scientists found that women whose vaginal tissue samples showed more signs of abnormality (an indication of higher and earlier exposure to the hormone) were more likely to experience these adverse events.