OBJECTIVE: To examine temporal trends in caesarean delivery rates in southern Asia and sub-Saharan Africa, by country and wealth quintile. METHODS: Cross-sectional data were extracted from the results of 80 Demographic and Health Surveys conducted in 26 countries in southern Asia or sub-Saharan Africa. Caesarean delivery rates were evaluated - as percentages of the deliveries that ended in live births - for each wealth quintile in each survey. The annual rates recorded for each country were then compared to see if they had increased over time. FINDINGS: Caesarean delivery rates had risen over time in all but 6 study countries but were consistently found to be lower than 5% in 18 of the countries and 10% or less in the other eight countries. Among the poorest 20% of the population, caesarean sections accounted for less than 1% and less than 2% of deliveries in 12 and 21 of the study countries, respectively. In each of 11 countries, the caesarean delivery rate in the poorest 40% of the population remained under 1%. In Chad, Ethiopia, Guinea, Madagascar, Mali, Mozambique, Niger and Nigeria, the rate remained under 1% in the poorest 80%. Compared with the 22 African study countries, the four study countries in southern Asia experienced a much greater rise in their caesarean delivery rates over time. However, the rates recorded among the poorest quintile in each of these countries consistently fell below 2%. CONCLUSION: Caesarean delivery rates among large sections of the population in sub-Saharan Africa are very low, probably because of poor access to such surgery.