England and Wales: distribution and results of hierarchical classifications tested by the Office for National Statistics

Objective To produce a classification of stillbirths registered in England and Wales compatible with a previously described classification for neonatal deaths; to compare national data for intrapartum stillbirths with those for the remaining stillbirths; and to report on stillbirths with a gestational age of 24 to 27 completed weeks first made registrable on 1 October 1992. Design Algorithms were developed and tested to derive hierarchical cause classifications making use of multiple causes mentioned on stillbirth certificates. Results The additional information available since 1986 on cause and time of death of stillbirths, classified in a hierarchical fashion allows a more meaningful interpretation of the available information on the causes of stillbirth than was previously possible and does not perturb ongoing trends. Antepartum deaths without a classifiable cause contributed the majority: between 1992 and 1994 they accounted for 43% if mentions of asphyxial conditions are regarded as classifiable causes, and 82% if not considered as causal. Stillbirths described as occurring intrapartum are consistently of higher gestational age and birthweight than the remainder, lending validity to the time of death given. Conclusions The national use of a classification including reported time of death of the fetus and mentions of asphyxial conditions is justifiable, providing a distinction is made between associated mentions and causal conditions. Better and more complete clinical information on stillbirth certificates will contribute further to understanding of their causes.