OBJECTIVE: To test the hypothesis that suboptimal factors in perinatal care services resulting in perinatal deaths were more common among immigrant mothers from the Horn of Africa, when compared with Swedish mothers. DESIGN: A perinatal audit, comparing cases of perinatal deaths among children of African immigrants residing in Sweden, with a stratified sample of cases among native Swedish women. POPULATION AND SETTING: Sixty-three cases of perinatal deaths among immigrant east African women delivered in Swedish hospitals in 1990-1996, and 126 cases of perinatal deaths among native Swedish women. Time of death and type of hospital were stratified. MAIN OUTCOME MEASURES: Suboptimal factors in perinatal care services, categorised as maternal, medical care and communication. RESULTS: The rate of suboptimal factors likely to result in potentially avoidable perinatal death was significantly higher among African immigrants. In the group of antenatal deaths, the odds ratio (OR) was 6.2 (95% CI 1.9-20); the OR for intrapartal deaths was 13 (95% CI 1.1-166); and the OR for neonatal deaths was 18 (95% CI 3.3-100), when compared with Swedish mothers. The most common factors were delay in seeking health care, mothers refusing caesarean sections, insufficient surveillance of intrauterine growth restriction (IUGR), inadequate medication, misinterpretation of cardiotocography (CTG) and interpersonal miscommunication. CONCLUSIONS: Suboptimal factors in perinatal care likely to result in perinatal death were significantly more common among east African than native Swedish mothers, affording insight into socio-cultural differences in pregnancy strategies, but also the suboptimal performance of certain health care routines in the Swedish perinatal care system.