Techniques to measure free-living energy expenditure during pregnancy - A guide for clinicians and researchers.

As maternal overweight and obesity increase in prevalence, the need to optimise gestational weight gain has entered the forefront due to the well-documented poor fetal and maternal outcomes associated with excess adipose tissue. Measurements of changes in energy expenditure form crucial components of effective weight management programmes, and they are also important for clarifying the energy requirements of pregnancy. This review evaluates the primary techniques for measuring free-living energy expenditure for use in pregnancy, with special consideration of the dynamic physiological changes that occur in this state. The methods that will be discussed include the doubly labelled water method, activity recall and activity logs, heart rate monitors and motion sensors. This article may be useful for clinicians seeking to implement active gestational weight management by enabling advice on increases in caloric intake linked to measured changes in energy expenditure, and for researchers studying energy metabolism in pregnancy.