A child's risk of dying is highest in the neonatal period, the first 28 days of life. About 3.3 million babies died in 2009 in their first month of life and 2.6 million are stillborn. Within the first month, one quarter to one half of all deaths occurs within the first 24 hours of life, and 75% occur in the first week. Preterm birth, birth asphyxia (lack of breathing at birth), and infections cause most neonatal deaths. From the end of the neonatal period and through the first five years of life, the main causes of death are pneumonia, diarrhoea, malaria, measles and HIV/AIDS. Malnutrition is the underlying contributing factor in over one third of all child deaths, making children more vulnerable to severe disease. In urban areas of Africa, Americas and Asia we can see that children in the poorest 20% population are twice as likely to die before their first birthday compared to children in the richest 20% population.
There has been progress in reducing infant mortality rates in urban areas of Africa, Americas and Asia. For example, the urban poorest 20% in Africa have witnessed a decrease in infant mortality rate from 99 per 1000 live births in the 1990s to 70 per 1000 live births in 2000-2007, on average. Similarly, the poorest 20% in urban areas of Asia have experienced a fall in infant mortality rates from 81 to 51 per 1000 live births between 1990s and 2000-2007, on average.