ESTIMATE OF PERINATAL-MORTALITY RISK

Perinatal mortality is usually calculated according to the World Healt h Organisation as stillbirth and first week mortality at a specified w eek of gestation divided by all births at that same gestational week. This is not a meaningful indicator of the risk of future perinatal dea th for a living fetus. We have developed an approach to estimate the p rospective risk of perinatal mortality. Data were derived from the Per inatal Database of the Netherlands. We calculated the prospective risk of perinatal mortality by dividing all future perinatal deaths from a certain week of gestation by all fetuses that remained undelivered. U sing this statistic there is a decline in risk from 16 to 39 gestation al weeks and an increase from 39 weeks onwards.