ABSTRACT
This chapter explores some of the perils and hazards of epidemiological studies on perinatal mortality. In general, the perinatal death rate tends to increase with advancing maternal age. The relationship between birthweight and perinatal mortality has been a major focus of interest of perinatal epidemiology for many decades. The pattern shown with birthweight is striking and similar for different countries and different ethnic groups within nations. Comparison of organ weights can show whether there has been chronic growth retardation and the gyral pattern will give a reliable estimation of gestation. The majority of authors who have assessed perinatal mortality rates in association with maternal education have found significant negative trends. The twinning rate varies across countries, almost all the variation being due to variation in dizygotic rather than monozygotic twinning.
