New Equation for the Prediction of Resting Energy Expenditure During Pregnancy

Objective: The equation for the prediction of resting energy expenditure (REE) during pregnancy is unknown. The aim of this prospective longitudinal study was to determine a new equation for prediction of REE in pregnancy.

Methods: A total of 152 randomly recruited healthy pregnant Czech women (nonsmokers, not users of chronic medications or abusers of alcohol or drugs, normoglycemic, euthyroid, and not anemic) were divided into two cohorts: group 1 (n=31) was used for determination of the equation for calculation of pregnant REE and group 2 (n=121) for cross-validation of this formula. The REE of the pregnant women in both study groups was examined by indirect calorimetry (REE-IC) along with anthropometry after 12h of fasting in four periods of pregnancy. A statistical comparison of three basic equations (Harris Benedict, Schofield, and Kleiber) was used for the prediction of REE.

Results: Through correlation analysis and linear regression, a new predictive equation of REE during pregnancy (P REE) was derived from the Harris Benedict equation. We observed high concordance between values from P REE and REE-IC in group 2. Analysis of alternative predictive equations of REE with the addition of kilocalories and a corrected multiplication factor for each stage of pregnancy expressed low concordance.

Conclusions: The equation for REE in kilocalories during pregnancy, P REE=346.43943+13.962564 x W + 2.700416 x H - 6.826376 x A (W, weight; H, height; A, age), with SD 116 kcal/d, corresponds closely to REE-IC and maternal changes in each phase of pregnancy. P REE can be applied for prediction of REE during gestation.