Extremely low birth weight and neonatal mortality measures
THE CONTEXT
These definitions distinguish a birth-weight category from measures of neonatal and perinatal mortality.
Extremely low birth weight
•
An extremely low birth weight neonate weighs less than 1000 g at birth, irrespective of gestational age.
Mortality measures
•
Neonatal mortality rate is the number of infant deaths during the first 28 days of life per 1000 live births per year.
•
Perinatal mortality ratio is the number of stillbirths plus neonatal deaths before 7 days of life per 1000 live births.
•
The perinatal measure is termed a ratio because its numerator is not part of its denominator. For a rate, such as neonatal mortality rate, the numerator must be part of the denominator.