INTRODUCTION: The aim of this report is to present descriptive data from the Swedish Medical Birth Register (MBR) reflecting trends in obstetric and neonatal practices over three decades. MATERIAL: Since 1973 the MBR at the Swedish National Board of Health and Welfare receives information on all pregnancies in Sweden--around 95,000 annually--that have lead to delivery regarding the pregnancy, delivery and the newborn infant. In this study selected data from the MBR are presented as they have developed between 1973 and 2000. RESULTS: There was a shift in age distribution of childbearing women towards older women. Cigarette smoking in early pregnancy decreased from 30% to 12%. In-hospital time after both vaginal and cesarean (CS) delivery decreased and more than 50% of all women with a vaginal singleton delivery left hospital within 48 hours in 2000. The proportion of CS increased from 5 to 15% at singleton deliveries. The CS rate for breech deliveries increased and was nearly 80% in 2000. The mean birth weight increased, particularly the proportion of heavy infants. The proportion of early neonatal deaths decreased continuously, both for term infants and infants born after short gestational length, whereas no such downward trends was found for stillbirth during the last 10-15 years. CONCLUSION: Although several of the changes regarding pregnancy and delivery that occurred between 1973 and 2000 could be expected to influence pregnancy outcome negatively, the trends described here generally suggest improvement in maternal and child health.