Objectives: To determine the incidence and causes of maternal mortality as well as its temporal distribution over the last decade (1990-1999). Study design: All maternal deaths recorded within the study period in the State of Kano, Northern Nigeria, were analyzed. Maternal mortality ratios (MMR) were computed using the Poisson assumption to derive confidence intervals around the estimates. A non-linear regression model was fitted to obtain the best temporal trajectory for MMR across the decade of study. Results: A total of 4154 maternal deaths occurred among 171621 deliveries, yielding an MMR of 2420 deaths per 100000. Eclampsia, ruptured uterus and anemia were responsible for about 50% of maternal deaths. Conclusion: We found one of the highest maternal mortality ratios in the world. Maternal mortality could be reduced by half at study site with effective interventions targeted to prevent deaths from eclampsia, ruptured uterus and anemia. © 2003 Elsevier Science Ireland Ltd. All rights reserved.