What is meant by infant mortality rate?

The infant mortality rate specifically refers to the number of deaths of infants under one year of age per 1,000 live births within a given year. This measure is a critical indicator of the overall health and well-being of a population, as it reflects factors such as maternal health, nutrition, access to sanitation, and the quality of medical care available. High infant mortality rates can signal underlying health problems in a community or country, making this statistic essential for policy-making and public health initiatives.

The other choices reflect different aspects of child health and demographics, but they do not correctly define the infant mortality rate. For instance, the first option focuses on children under five, which broadens the age range and diverges from the specific definition. The average lifespan of infants pertains to different population health metrics, such as life expectancy, and does not relate directly to mortality rates. Lastly, the number of infants born per year relates to birth rates and does not address deaths, which is the core of what the infant mortality rate measures.