Oral contraceptives, venous thromboembolism, and the courtsBMJ 2002; 325 doi: https://doi.org/10.1136/bmj.325.7363.504 (Published 07 September 2002) Cite this as: BMJ 2002;325:504
There has to be a better way of resolving claims about adverse effects
- David C G Skegg, professor. (firstname.lastname@example.org)
- Department of Preventive and Social Medicine, University of Otago, PO Box 913, Dunedin, New Zealand
Controversy is an inevitable element of medical progress, but sometimes it degenerates into doubtful disputations. During the 1950s, as evidence mounted about the exceptionally strong association between smoking and lung cancer, ingenious theories were advanced about bias or confounding in the epidemiological studies. Sir Ronald Fisher, the renowned statistician, described the notion that cigarettes can cause lung cancer as “a catastrophic and conspicuous howler.” 1 It is small wonder that consensus is slow to develop about much weaker associations between drugs (or contraceptives) and adverse events. A recently completed trial in the English High Court raises the question of whether the judicial process can help us reach sensible conclusions.
The action was brought against three pharmaceutical companies by women who believed they had been harmed by third generation oral contraceptives. In October 1995, the United Kingdom's Committeeon Safety of Medicines announced that such contraceptives (containing desogestrel or gestodene) carried a higher risk of venous thromboembolism than older formulations (containing levonorgestrel).Controversy raged for several years and, although the evidence has convinced many expert bodies—including a scientific group at the World Health Organization2 and the European Agency for the Evaluation of Medicinal Products3—the manufacturers and their …