Tehran University of Medical Sciences Acta Medica Iranica 0044-6025 47 4 2009 08 15 319 324 EN Marzieh Nojomi Department of Community Medicine, School of Medicine, Iran University of Medical Sciences, Tehran, Iran. Morteza Naserbakhat Department of Community Medicine, School of Medicine, Iran University of Medical Sciences, Tehran, Iran. Mojdeh Ramezany Department of Community Medicine, School of Medicine, Iran University of Medical Sciences, Tehran, Iran. Khatereh Anbary Department of Community Medicine, School of Medicine, Iran University of Medical Sciences, Tehran, Iran. 2015 09 28 In July 2003, the Bellagio Study Group on Child Survival estimated that the lives of 6 million children could be saved each year if 23 proven interventions were universally available in the 42 countries re-sponsible for 90% of child deaths in 2000. The aim of this study was to determine frequency of important causes of mortality among under-5 year old children in hospitals, Tehran, Iran. Information about Mortality data of under-5 year old children from 16 hospitals in the West of Tehran was collected. The study period was conducted from 1 October 2005 to 30 March 2006. Educated health personnel in each hospital interviewed parents of children who died in hospital and filled out a checklist. 142 under-5 year old children died over the course of study, of whom, 118 (83%) were neonates (under 28 days-old), 53.5% had low birth weights (< 2500 Kg), 62 (43%) were girls and 80 (57%) boys. The most common cause of under-5 year death was due to certain conditions originating in the perinatal period (ICD-10: P00-P96) (68%). Congenital abnormalities (12%) and pneumonia (5%) were the second and third most common causes respectively. Among 28-day to one-year old children, the leading cause of death was pneumonia (27.3%), while for children being 1 to 5 years of age, this included pneumonia and chronic hepatitis (about 30%). Overall, the most common causes of death were disorders related to short gestation and low birth weight. Therefore, achievement of the millennium development goal of reducing child mortality by two-thirds from 1990 rate will depend on renewed efforts to prevent and control low birth weight, preterm delivery, pneumonia, and infectious diseases in our setting. https://acta.tums.ac.ir/index.php/acta/article/view/3599 https://acta.tums.ac.ir/index.php/acta/article/download/3599/3575