The majority of the 82 cases of tubal choriocarcinoma reported in the published literature followed malignant transformation of a tubal ectopic pregnancy. The case presented was not related to ectopic pregnancy but was apparently the result of malignant changes in migrating trophoblastic elements during previous pregnancies not arriving at full term. The patient had two abortions by aspiration and had been on oral contraceptives ever since. Fifteen or so of the cases of extra-uterine choriocarcinoma published in the literature appear to have resulted from the same aetiopathogenic mechanism.