At 5.3 per 1,000 live births, the infant mortality rate was the lowest level ever recorded. The most frequent cause of infant deaths was congenital anomalies. To assist in the interpretation of trends, most time series tables in this report show figures based on both the old and the new definitions. Some further information on stillbirths may be found in Tables 3.11 and 3.12 . Perinatal deaths refer to stillbirths and deaths in the first week of life.
Neonatal deaths refer to deaths in the first four weeks of life.
Postneonatal deaths refer to deaths after the first four weeks but before the end of the first year. Infant deaths refer to all deaths in the first year of life. Commentary Numbers and rates Tables 4.1 and 4.2 give numbers and rates for the various categories of stillbirths and infant deaths since 1946. Some relevant figures are also given for 1992 to 1997 using the old definition of stillbirth. The infant mortality rate was 5.3 per 1,000 live births, compared with a rate of 6.2 for the previous three years and 8.5 for ten years previously.