61 cases of gestational trophoblastic disease (GTD) were examined retrospectively in the period 1976-89 (60 cases of simple vesicular mole and one case of chorionepithelioma), analysing them from the epidemiologic point of view. The incidence of GTD were 3.6/1000 live births, higher than the Italian and European average, with a very low incidence, on the contrary, of chorionepithelioma (0.06/1000 live births). No significant epidemiological data emerged, with the exception of age (11 cases of over 40 years) and of ABO typing (a notable incidence of ORh + group). The gestational capacity of the patients returning for checking was 78.9%, similar to that of the general population.