STUDY OBJECTIVE--To study whether hospitals of different levels are equally safe places to give birth in a regionalised system of care. DESIGN--This was a population based, cross sectional survey comparing birth outcomes in nationwide catchment areas of different levels of hospital care. All women and low risk women were examined separately. SETTING AND SUBJECTS--The study population comprised all women who gave birth in Finland in 1987-88. The data were obtained from the Finnish Medical Registry, complemented by official data. MAIN RESULTS--No statistically significant differences were found in crude or birthweight specific perinatal mortality rates between the catchment areas, nor did the other outcomes studied favour tertiary care compared with other levels of care in the area based analysis. CONCLUSIONS--In a regionalised system of birth care with a proper referral system, small local hospitals are as safe places to give birth as tertiary care hospitals.