STUDY OBJECTIVE: To identify variables available in early Swedish delivery records and their relation to birth outcomes for home and hospital deliveries in Gothenburg at the early part of this century. DESIGN: A retrospective recovery of original delivery records and social variables in a cross sectional population. SETTING: Gothenburg, Sweden. PARTICIPANTS: 851 fullterm singleton female births with known gestational age born into five birth cohorts on selected dates (1908, 1914, 1918, 1922 and 1930). MAIN RESULTS: Delivery site, maternal parity, gestational age, and social group were significant factors influencing birth outcome as birth weight and length. The mean birth weight and length of hospital born infants was consistently lower than for home deliveries across all cohorts. Site of delivery changed significantly during the period of births under study, 1908-1930. CONCLUSIONS: In this study, which was based on original delivery records from the early part of this century, it was found that delivery site was an important factor influencing birth outcome across five birth cohorts. Utilisation of delivery services changed during the period of study. Thus, to avoid selection bias, the application of delivery records should reflect the birthing practice of the time period in question.