Body Mass Index (BMI)
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An indirect measure of body fat. Identifies possible weight problems for adults, and allows individuals to compare their weight status to that of the general population. BMI = weight(kg)/height(m2).
Interpretation of BMI in adults
Overweight - BMI of 25-29.9 kg/m2
Obesity l - BMI of 30-34.9 kg/m2
Obesity ll - BMI of 35-39.9 kg/m2>?p>
Obesity lll - BMI of 40 kg/m2 or more
BMI takes no account of fat distribution or body composition; for example, a highly trained athlete may have a high BMI because of increased muscularity rather than increased body fat.
National Institute of Health and Care Excellence (2010). Weight management before, during and after pregnancy. Public Health guideline 27. https://www.nice.org.uk/guidance/ph27
National Institute of Health and Care Excellence (2014). Obesity:identification, assessment and management. Clinical Guideline 189. https://www.nice.org.uk/guidance/cg189
Royal College of Obstetricians and Gynaecologists. (2010). Management of women with obesity in pregnancy. https://www.rcog.org.uk/en/guidelines-research-services/guidelines/management-of-women-with-obesity-in-pregnancy/
NHS Choices. Overweight and pregnant (2015) http://www.nhs.uk/conditions/pregnancy-and-baby/pages/overweight-pregnant.aspx
Royal College of Obstetricians and Gynaecologists. (2011) Why your weight matters during pregnancy and after birth. https://www.rcog.org.uk/en/patients/patient-leaflets/why-your-weight-matters-during-pregnancy-and-after-birth/