Comparing perinatal mortality

Comparisons of perinatal outcome data among regions or hospitals can be misleading if the risk status of the population served is not considered. Data are presented from two large perinatal centers (Medical Center Hospital in San Antonio, Texas, and University of Iowa Hospitals in Iowa City, Iowa), which report substantially different institutional neonatal and fetal mortality rates. However, examination of neonatal and fetal mortality by birth weight groupings demonstrates the difference between outcome in the two hospitals to be considerably less than the overall rates might imply. Additional data about the regionalized system of care in Iowa are presented to illustrate why mortality may rise in a referral center and yet be consistent with a salutary effect on perinatal outcome in the region.