Maternal smoking and the epidemic of testicular cancer--a nested case-control study

For no apparent reason, the incidence of testicular cancer has increased to epidemic proportions in many countries. Pregnancy smoking has been suggested to be a cause. Previous analytical studies have been negative, but the inherent difficulties in retrospective assessment of this exposure have led to no definite conclusion. We have conducted a population-based case-control study on 192 cases of testicular germ-cell cancer-born in Sweden in 1973 onwards and aged >=15 at cancer diagnosis-and 494 matched controls, where data on maternal smoking were collected during pregnancy. We found no association with testicular cancer for maternal smoking during pregnancy (OR, 0.91; 95% CI, 0.64-1.30), and there was no evidence of a dose-response effect. We conclude that the epidemic rise in testicular cancer in many populations is not due to the surge in smoking among women.