Effect of nonviable infants on the infant mortality rate in Philadelphia, 1992.
OBJECTIVE
This report measured the effect of births at 22 weeks' gestation or earlier on infant mortality in Philadelphia, Pa.


METHODS
The proportion of live-born deliveries at 22 weeks or earlier was calculated. Overall and race-specific infant mortality was calculated after excluding live-born deliveries at 22 weeks' gestation or earlier.


RESULTS
Of all deliveries, 1.5% were at 22 weeks or earlier. Of these, 68% were stillborn and 32% were live-born. Large hospital-to-hospital variation in the proportion of live-born deliveries at 22 weeks' gestation or earlier was noted. When nonviable births were excluded, overall infant mortality decreased 40%.


CONCLUSIONS
The development of a standardized birth certificate policy is needed and will facilitate comparisons of infant mortality across spatial boundaries and racial/ethnic groups.
Gibson
E
E
Division of Neonatology, Thomas Jefferson University, Philadelphia, Pa. 19107, USA. eric.gibson@mail.tju.edu
Culhane
J
J
Saunders
T
T
Webb
D
D
Greenspan
J
J
D001719:Birth Certificates; D001724:Birth Weight; D005260:Female; D005313:Fetal Death; D005865:Gestational Age; D006801:Humans; D007226:Infant Mortality; D007231:Infant, Newborn; D016015:Logistic Models; D008423:Maternal Age; D015143:Philadelphia / Q000453:epidemiology; D044469:Racial Groups