The number of children and infants dying before they reach the age of five is startling. While child mortality varies around the world, 5.9m children under the age of five died in 2015. More than half of these early deaths were due to preventable diseases or treatable conditions, such as diarrhoea or malnutrition. This means the deaths are caused by socio-economic marginalisation and by barriers in access to simple, affordable healthcare.

In a new study, my colleagues and I looked at data for 194 countries and found that a country’s rate of gender inequality is associated with a higher level of child mortality, with girls being disproportionally affected, in particular in low and middle-income countries.

Globally, children are at a greater risk of dying before age five if they are born in rural areas, within poor households, and if their mother was denied basic education. Gender has an impact on access to social power, which in turn interferes with the decision-making process and the distribution of resources within households. In some countries, men and women’s lives can be valued differently too.

While around 107 boys are born for every 100 girls globally, boys experience a higher mortality in early infancy. This has been linked to greater biological susceptibility of boys to diseases. For example, girls are less vulnerable than boys to perinatal conditions, congenital anomalies, and infectious diseases.

Worldwide, at country level, an average of 120 boys died in 2015 per 100 girls before reaching age five. That year child mortality before age five was higher among boys compared to girls in all countries in the world except for Tonga and India, where 81 and 94 boys were dying for each 100 girls, respectively.

The highest mortality among boys compared to girls under the age of five was registered in Mongolia (148 boys per 100 girls), Turkmenistan (144 boys), and Vietnam (140). The number of boys dying compared to girls was higher in upper-middle and high-income countries, but a clear pattern among countries worldwide was not immediately evident. The map below divides the countries in the world into four groups according to an under-five mortality sex ratio. The palest green indicates countries where 117 boys or less died for each 100 girls, with 124 boys or more per 100 girls dying in the darkest green countries.

The under-five mortality rate per 1,000 live births sex ratio, adapted from UNICEF data for 2015. Author provided (No reuse)

Mapping gender inequality

Our study compared this data on under-five mortality with a global index of gender inequality, published by the UN Development Programme. The Gender Inequality Index(GII) measures gender inequalities in three aspects of human development: reproductive health, empowerment, and economic status. It reflects the human development costs of gender inequality, which has been associated with higher infant mortality. This can be partially explained by a number of cultural, societal, and economic factors, such as the wealth of a country and access to healthcare.

In the graph below, we plotted the under-five mortality rates per boys (green dots) and girls (blue dots) against GII. We’ve shown how, overall, under-five mortality increases in countries where gender inequality is higher – for example, countries such as Yemen or Tonga on the right-hand side of the graph. However, we noticed that some countries had larger differences between boy and girl mortality, compared to others.

The association between the Gender Inequality Index on the x-axis and male (green) and female (blue) under-five mortality rate on the y-axis, at country level, worldwide. Author provided (No reuse)

Girls at greater risk

Our analysis also shows that gender inequality in a country is associated with disproportionate death rates among girls under five-years-old, compared to boys. So the higher the GII of a country, the lower the under-five mortality sex ratio, implying that relatively fewer boys died compared to girls.

In the graph below, gender inequality is shown on the horizontal axis (with more equal countries on the left hand side), and the boy to girl under five-mortality ratio is shown on the vertical axis (1.2 representing the average of 120 boys dying for every 100 girls). Each dot represents a country, showing that in low- and middle-income countries (the light blue and pale green cloud of dots) higher gender inequality is correlated with relatively fewer boys dying for every 100 girls.

The association between the Gender Inequality Index (GII) on the x-axis and male to female under-five mortality rate on the y-axis, at country level, worldwide. Author provided (No reuse)

Given the specific design of our study, we weren’t able to say that the girls who die under the age of five do so as a result of gender inequality in each country. There may also be other factors that influence the association we found.

However, gender inequality may contribute to the likelihood of a boy surviving beyond age five compared to a girl, through its impact on mothers. Maternal under-nutrition, exposure to violence, and lack of access to education can leave children experiencing poorer health. This could be through susceptibility to communicable diseases such as respiratory tract infection, or birth complications, as well as reduced access to preventive medicine.

In order to decrease child mortality in general, policies should be extended to focus beyond economic development towards reducing gender inequality across a variety of domains, including healthcare, education, workforce participation and political empowerment. Only until these measures are addressed will the detrimental transgenerational effects of gender inequality on child mortality, and particularly the child mortality of girls, be alleviated.

Written by Valentina Gallo, Senior Lecturer in Epidemiology, Queen Mary University of London