Energy expenditure in healthy pregnant women: a systematic review.

Context: Since pregnancy is a decisive period for women and children in terms of future health, it is very important to determine changes in energy expenditure and requirements. However, there is no reference method to determine the energy expenditure as there are many factors that change maternal energy homeostasis during this period.

Objective: This review aims to evaluate the changes in energy expenditure during pregnancy and the effects of these changes on maternal weight gain, as well as the methods used to determine energy expenditure.

Data Sources: Google Scholar, PubMed, ScienceDirect, Cochrane Library, and Wiley Online Library databases were searched to determine studies on energy expenditure during pregnancy between 2010 and 2022.

Data Extraction: Of the 2095 articles initially identified, 20 met the inclusion criteria for this review. Two independent reviewers selected and extracted data from those articles.

Data Analysis: The articles reviewed show that prepregnancy body mass index, gestational weight gain, changes in fat mass, and lean body mass influence energy expenditure during pregnancy. Doubly-labeled water and indirect calorimetric methods are considered reference methods for determining energy expenditure in pregnancy. Indirect calorimetric methods, when used together with body weight and physical activity measurements, allow an accurate estimation of resting energy expenditure and energy requirements for pregnant women. Metabolic Holter or accelerometers are valid methods for determining activity energy expenditure in pregnant women and are suitable for use during activity.

Conclusion: Resting energy expenditure and activity energy expenditure should be carefully monitored and measured by valid methods to achieve the correct energy intake targets during pregnancy. The existing equations used in determining energy expenditure should be developed for a more accurate estimation of energy expenditure during pregnancy, or new pregnancy-specific equations should be derived.