Perinatal Statistics of Registry Hospitals of Japan in 1974 to 1978 by The Committee on Perinatal Statistics of the Japan Society of Obstetrics and Gynecology

Annual reports of perinatal statistics in Japan from about 200 registry hospitals are summarized. A gradual decrease in the perinatal mortality rate has been observed from 16.04 in 1974 to 13.50 in 1978. Among the initially registered 129 hospitals, a similar decrease in perinatal mortality has been observed. Among the 18 main clinical causes of death, the percentages of placenta previa and neonatal respiratory distress exhibited a decrease during the last 5 years. Among the cases of perinatal death, in member hospitals of the Committee on Perinatal Statistics, three criteria were used to determine the perinatal stage for purposes of comparison, namely: 1) a gestational age of 28 or more weeks, or alternatively, birthweights of 2) 500 to 999.9 g or 3) 1000 g or more. Perinatal mortality was lowest in the group weighing 1000 g or more (9.87), slightly higher in the group aged 28 weeks or more (10.94) and highest in 500 to 999.9 g group (14.40). Individual case reports of perinatal death in member hospitals of the Committee are analyzed, and an ICD-based investigation elucidated the characteristic patterns of perinatal death.