<Tr> <Td> </Td> <Td> This article is written like a personal reflection or opinion essay that states a Wikipedia editor's personal feelings about a topic . Please help improve it by rewriting it in an encyclopedic style . (April 2015) (Learn how and when to remove this template message) </Td> </Tr> <P> Infant mortality refers to deaths of young children, typically those less than one year of age . It is measured by the infant mortality rate (IMR), which is the number of deaths of children under one year of age per 1000 live births . The Under - Five Mortality Rate is also an important statistic considering the Infant Mortality Rate has a strict limit on focusing on children only under one year of age . it is the number of deaths of children below 1 year by the number of 100 live children's born </P> <P> Premature birth is the biggest contributor to the IMR . Other leading causes of infant mortality are birth asphyxia, pneumonia, term birth complications such as abnormal presentation of the foetus umbilical cord prolapse, or prolonged labor, neonatal infection, diarrhea, malaria, measles and malnutrition . One of the most common preventable causes of infant mortality is smoking during pregnancy . Many factors contribute to infant mortality, such as the mother's level of education, environmental conditions, and political and medical infrastructure . Improving sanitation, access to clean drinking water, immunization against infectious diseases, and other public health measures can help reduce high rates of infant mortality . </P> <P> Child mortality is the death of a child before the child's fifth birthday, measured as the Under - 5 Child Mortality Rate (U5MR). National statistics sometimes group these two mortality rates together . Globally, 9.2 million children die each year before their fifth birthday; more than 60% of these deaths are seen as being avoidable with low - cost measures such as continuous breast - feeding, vaccinations and improved nutrition . </P>

What is the leading cause of infant death in the united states
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