Common Pesticide May Reduce Fertility In Women

The researchers found that MXC, which was manufactured as a saferreplacement for the now-banned DDT, alters the estrogen-regulated geneHoxa10 in the reproductive tract and reduces the ability of the uterusto support embryo implantation. The researchers used mice and thenhuman cell lines to confirm their findings.

MXC is a man-made pesticide used to kill flies, mosquitoes,cockroaches and other insects, and is applied directly to food crops,livestock, home gardens and pets. It is one of a large number ofchemicals that can mimic the action of hormones and in some instancesinterfere with endocrine function.

Some of these endocrine disruptors bind estrogen receptors andadversely affect reproductive tract development, which is heavilyinfluenced by estrogen. MXC and other chemicals like DDT have beenshown in other studies to induce abnormalities in tissue developmentand function in the female reproductive tract.

"MXC has an adverse effect on these mice similar to that ofDES, a synthetic estrogen," said senior author Hugh S. Taylor, M.D.,associate professor in the Division of Reproductive Endocrinology andInfertility in the Department of Obstetrics, Gynecology &Reproductive Sciences at Yale School of Medicine. "Female offspring ofwomen exposed to DES were more likely to have an abnormally shapedcervix, were more prone to cancer of the vagina, miscarriages, earlylabor and other complications."

Other authors on the study included Xiaolan Fei and Hajin Chung

Citation: Endocrinology, 146: 3445-3451 (August 2005)