Background: The results of changes in perinatal health care in Maribor show a significant improvement in the past decade. Between 1995 and 1999, the survival chances of neonates with birth weight < 1000g also increased. With the appearance of new generations of extremely low-birth-weight infants, the risk of a higher incidence rate of various forms of neurosensory affection in the survivors increased.
Methods: We determined trends in the incidence of cerebral palsy (CP) in live birth and one-year survivor cohorts of children in the Maribor region for the decade 1988-1998. We identified children with CP in the Maribor region by record review as part of an ongoing developmental disability surveillance program conducted by the Centers for children with developmental disturbances at the Public Health Centers of the Maribor region (Maribor, Lenart, Ptuj, Ormoz and Slovenska Bistrica). A total of 123 cases of congenital CP were identified for the birth years 1988-1998. Data were analyzed according to birth weight, gestational age, subtypes of CP, and whether CP existed as an isolated disability or was accompanied by another disability. We compared the data for 1988-1993 with those of 1994-1998.
Results: There was a modest increase in the overall incidence of congenital CP from 3.7 to 4.3 per 1000 one-year survivors during the second part of the 1988-1998 decade. This trend was primarily attributable to an increase in CP in children with low or extremely low birth weight. There was an increase in the proportion of children who had both CP and other disabilities, most apparent in infants with birth weight > 2500g, from 53% in 1988-1993 to 62% in 1994-1998. For children weighing < 1500g, the proportion of children with spastic diplegic CP increased during the decade (62% in 1988-1993 and 78% in 1994-1998); for children weighing > 2500g, the proportion with spastic diplegia decreased (62% in 1988-1993 and 44% in 1994-1998).
Conclusion: In a decade in which perinatal mortality was halved and survival among neonates with birth weight under 1500g increased to 90% in the second part of the decade, the average incidence of CP in the Maribor region increased slightly from 3.7 per 1000 survivors in 1988-1993 to 4.3 per 1000 survivors in 1994-1998. This increase was seen in infant survivors with birth weight < 1500g. Although no change was seen in the trends in CP incidence in low-birth-weight infants, a decrease was seen in infant survivors with birth weight > 2500g.