Infant mortality rate – The average number of deaths of infants under one year of age per 1,000 live births per year

To remember the meaning of the term Infant Mortality Rate, use the following mnemonic:

A one-year-old (one year of age) lifting a one-ton or 1,000kg weight (per 1,000 babies) – this should remind you that the infant mortality rate is the number of babies under one year old who die per 1,000 live births per year.

The infant mortality rate is one of the vital markers of the overall health of a country's population.

Generally speaking, the poorer a country, the higher its infant mortality rate is likely to be.

For instance, in 2019 the rate in Angola, Africa, was 50.2 deaths per 1,000 live births; in Japan in the same year, the rate was just 1.8 in 1,000.

In Victorian England, the infant mortality rate averaged around 150 per 1,000 live births, whereas in 2020, the rate for the UK was about 3.6 deaths per 1,000 live births, illustrating the improvements that have been made over time.

However, both the UK and U.S. rates are higher than in many other developed countries. The U.S. rate was about 5.7 in 2020.