Diethylstilbestrol (DES) Litigation Lawsuit

Diethylstilbestrol (DES) Litigation

The product

Diethylstilbestrol, commonly called DES, is a synthetic nonsteroidal estrogen first synthesized in 1938 and introduced for medical use in 1939. Because the compound was never patented, it was produced by more than two hundred pharmaceutical and chemical companies, most of them using the same basic formula. The U.S. Food and Drug Administration approved it in 1941, and in 1947 it approved DES for use during pregnancy to prevent miscarriage. From the 1940s until 1971, the drug was widely prescribed to pregnant women, on the then-prevailing belief that it reduced the risk of pregnancy complications and losses. Sales peaked in 1953, and the estimated number of people exposed in utero or during pregnancy in the United States during that era may be as high as 2,000,000.

The discovered harm

In 1971, a report in the New England Journal of Medicine established a probable link between in-utero DES exposure and clear-cell adenocarcinoma, a rare vaginal cancer, in daughters of women who had taken the drug. That year the FDA issued a Drug Bulletin advising physicians against prescribing DES in pregnancy, removed the miscarriage-prevention indication, and added pregnancy as a contraindication; the higher-strength tablets were withdrawn from the market in 1975.

Follow-up research over subsequent decades identified a broader set of problems. Exposed daughters ("DES daughters") and sons showed an increased incidence of vaginal adenosis, a T-shaped uterus, cervical weakness, infertility, and other reproductive abnormalities. DES mothers have an elevated risk of breast cancer, and animal work suggests the possibility of transgenerational effects, though the extent of those effects in humans remains unclear.

The litigation

The 1971 findings triggered a large wave of U.S. litigation against DES manufacturers. Two features made the cases unusually difficult. First, because hundreds of companies had produced identical products, plaintiffs generally could not show which specific manufacturer had supplied the drug taken by their mothers; many successful recoveries therefore relied on theories of joint or several liability. Second, in 1980 the California Supreme Court in Sindell v. Abbott Laboratories adopted a market-share liability rule for these cases, imposing a rebuttable presumption of liability on all DES makers apportioned according to each company's share of the market at the relevant time.

A separate line of claims arose from a 1950s University of Chicago clinical trial. Women who had participated in the trial and their children alleged injury, including failure to warn of the drug's risks. In Mink v. University of Chicago, the court declined class certification and dismissed the warning and strict-liability claims, but the battery allegations survived; the dispute was resolved through a pre-trial settlement under which the university agreed to provide medical examinations to trial participants' DES-exposed offspring.

As of early 1991, more than a thousand actions against DES makers were still pending. A later group of breast-cancer cases, brought by women who said their cancers resulted from prenatal DES exposure, survived a Daubert evidentiary hearing and proceeded to trial.

Resolution

In 2013, the lead breast-cancer case was settled on the second day of trial. The remaining litigants were resolved through separate settlements, ending the principal lines of DES products liability litigation.