The pattern of hydatidiform moles in Singapore.

Hydatidiform mole is common in Singapore, and the the incidence of malignant trophoblastic neoplastic neoplasia is significantly higher than in Western countries. Within a 10-year period (1968-1977), 538 cases of hydatidiform mole were diagnosed. On retrospective study, 498 (92.6%) were considered to be complete and 40 (7.4%) partial. The ratios of complete to partial moles were similar for the major population groups. In the present study, only complete moles were found to give rise to persistent trophoblastic disease. The lack of such association in partial hydatidiform moles is in keeping with their known low malignant potential. Occasional abnormal post-evacuation hCG curves, however, are being described from other centres, and while the underlying pathology remains largely undocumented, partial moles have to be dealt with on an empirical basis in the light of the hCG follow-up levels.