The number of deaths of infants under one year of age. The IMR in any given year is calculated as the number of deaths in the first year of life in proportion to every 1,000 registered live births in that year. Along with PERINATAL MORTALITY, it is accepted as one of the most important criteria for assessing the health of the community and the standard of the social conditions of a country.
The improvement in the infant mortality rate has occurred mainly in the period from the second month of life. There has been much less improvement in the neonatal mortality rate – that is, the number of infants dying during the first four weeks of life, expressed as a proportion of every 1,000 live births. During the first week of life the main causes of death are asphyxia, prematurity, birth injuries and congenital abnormalities. After the first week the main cause of death is infection.
Social conditions also play an important role in infant mortality. In England & Wales the infant mortality rate in 1930–32 was: Social Class I (professional), 32.7; Social Class III (skilled workers), 57.6; Social Class V (unskilled workers), 77.1. Many factors come into play in producing these social variations, but overcrowding is undoubtedly one of the most important.
1851–60 | 154 | 1950–52 | 30 |
1910–12 | 110 | 1960–62 | 22 |
1920–22 | 82 | 1970–72 | 18 |
1930–32 | 76 | 1980–82 | 12 |
1940–42 | 59 | 1990–92 | 7 |
2007 | 4.8 | 2015 | 3.6 |
Infant mortality rate in the United Kingdom 1838–2015. Deaths of infants under 1 year of age per thousand live births. | |||
To reduce infant mortality rate to a minimum figure, the following conditions must be met. Mothers and potential mothers must be housed adequately in healthy surroundings, particularly with regard to safe water supplies and sewage disposal. The pregnant and nursing mother must have an adequate diet. Effective antenatal supervision must be available to every mother, as well as skilled supervision during labour (see PREGNANCY AND LABOUR). The newborn infant must be adequately nursed and fed and mothers encouraged to breast feed. Environmental and public-health measures must be taken to ensure a clean milk supply and full availability of medical care, including such protective measures as IMMUNISATION against diphtheria, measles, poliomyelitis, whooping-cough, and meningitis and septicaemia due to Haemophilus influenzae, meningococci and pneumococcus. (See also PERINATAL MORTALITY.)