Aim: To investigate the effect of maternal, infant and birth hospital district related factors on the length of initial hospital stay in very preterm infants. In addition, rehospitalization rate within the first year from the initial discharge was studied.
Methods: A register study covering all very preterm infants (gestational age < 32 weeks or birthweight < 1501 g) born alive in Finland between years 2000 and 2003 (N = 2148). Factors affecting length of stay (LOS) were studied using generalized linear model (GLM).
Results: The proportion of very preterm infants born in a level III unit varied in the hospital districts from 53% to 94%. Median LOS was 53 days (interquartile range: 38-76). There were large regional differences in the LOS, the difference being up to 10.5 days among the hospital districts (p < 0.0001). Rehospitalization rate was 47.2% within the first year from the initial discharge, and the absence of rehospitalization was associated with a 4.1 days shorter initial LOS (p < 0.0001).
Conclusion: Our study showed large regional variation in LOS of very preterm infants despite similar case mix. We speculate that the variation depends on differences in treatment practices and discharge criteria.