the reduction of infant mortality has been slower in india the russian federation and the united states significant differences are also evident in infant mortality rates among various racial groups in the united states with africanamerican women more likely to give birth to highrisk low birthweight infants nchs data for are not available for israel and south africa other factors such as better nutrition sanitation and housing also play a role particularly in countries with developing economies there are also notable differences in life expectancy between oecd countries with similar incomes per capita such as japan and denmark