Trophoblast Research 13: 171-177, 1999 PREVALENCE OF GESTATIONAL TROPHOBLASTIC DISEASE IN TAIWAN Su-Cheng Huang', Bor-Ching Sheu ~, Pao-Ling Torng 1, Cheng-Wei Tsai ~, Ruey-Jian Chen 1, Yu-Shih Yang ~, Ruey-Shyang Shyu:, Hong-Der Tsai 3, Guang-Perng Yeh ~ 'Department of Obstetrics and Gynecology National Taiwan University Hospital No. 7, Chung-Shan S. Road Taipei, Taiwan, 100 2Provincial Tao-Yuan Hospital Tao-Yuan, Taiwan ~'China Medical College Hospital Taichung, Taiwan ~Changhua Christian Hospital Changhua, Taiwan INTRODUCTION It is well known that gestational trophoblastic disease (GTD) has a striking geographical occurrence in Asia and developing areas (Wei and Ouyang, 1963; Wei and Ouyang, 1967; Kim et al., 1998a). Taiwan has an apparently high historical incidence of GTD (Wei and Ouyang, 1963; Hsu et al., 1964). Previous studies from Taiwan have used chemotherapy to treat GTD (Wei and Ouyang, 1967). A GTD scoring system was established in our hospital in 1980, which incorporates treatment strategy for different risk groups of patients (Ouyang et al., 1987). The advent of biomedical and clinical profiles has enabled effective diagnosis and treatment of GTD (Newlands et al., 1998; Lewis, 1998; Kim et al., 1998b). Recent reports suggest that the general incidence of GTD is decreasing in many Asian countries (Song and Wu, 1987; Registration Committee for Trophoblastic Disease of the Japan Society of Obstetrics and Gynecology, 1987; Hando et al., 1998; Kin~ et al., 1998a). This suggests that the socio-economic status of developing countries has some influence on the incidence of GTD (Song and Wu, 1987; Lewis, 1998; Hando et al., 1998; Kim et al., 1998b). However, no population-based survey on the general incidence of GTD in Taiwan area has been reported. Since Taiwan accounts for a significant role in the geographical prevalence of GTD, this study sought to compile a set of GTD data for Taiwan through a longitudinal survey of the incidence of GTD. Special attention was given to the factors which were likely to confound the analysis of GTD incidence. The GTD scoring system and treatment modalities with collaborative incidence are also evaluated in this study. The result of this study may improve our understanding of the prevalence of GTD in Asian populations. 171 9 of Rochester