PURPOSE: The purpose of this study is to examine the impact of prenatal ultrasonography (US) on the birth of babies with diseases listed on the Korean pediatric surgery index diseases (IDs). METHODS: Depending the ease of diagnosis using prenatal US, [diagnostic facility if prenatal US] IDs were divided into easily diagnosed (ED), not easily diagnosed (NED) and detected with difficulty (DD) groups. Five-year data were obtained for the total live birth number (TBN) from the Korean Statistical Information Service, and the actual birth number of IDs (ABNID) from the Korean Health Insurance Review and Assessment Service. The certified incidences of IDs (I) were obtained from a prestigious textbook of pediatric surgery. The estimated abortion rate (AR) of fetus in each group was obtained using the following formula: AR (%) = [1 - (ABNID)/(TBN x I)] x 100. RESULTS: The AR with all IDs was 38 to 77%. The AR was 78 to 93% for ED group, 38 to 66% for NED group and 0% for DD group. CONCLUSION: In spite of high survival rates after treatment, the AR of each group depends on the ease of diagnosis using prenatal US in Korea. A recommendatory policy for the fetus with IDs should be urgently established after general consensus within the related medical societies.