For live births, birthweight should preferably be measured within the first hour of life before significant postnatal weight loss has occurred. While statistical tabulations include 500 g groupings for birthweight, weights should not be recorded in those groupings. The actual weight should be recorded to the degree of accuracy to which it is measured.
In perinatal collections the birthweight is to be provided for liveborn and stillborn babies.
Weight on the date the infant is admitted should be recorded if the weight is less than or equal to 9000g and age is less than 365 days.