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ARS Home » Plains Area » Houston, Texas » Children's Nutrition Research Center » Research » Publications at this Location » Publication #102208
Title: LONGITUDINAL ASSESSMENT OF ENERGY BALANCE IN WELL-NOURISHED, PREGNANT WOMEN

Author
item KOPP-HOOLIHAN, LORI - DAIRY COUNCIL OF CALIF
item VAN LOAN, MARTA - USDA SAN FRANCISCO
item Wong, William
item KING, JANET - USDA SAN FRANCISCO

Submitted to: The American Journal of Clinical Nutrition
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/3/1998
Publication Date: N/A
Citation: N/A

Interpretive Summary: Pregnancy requires certain amounts of energy at conception, for maternal fat storage, and for basal metabolism to maintain new tissue. Doctors often recommend to pregnant patients that in order to meet their increased energy needs, they should eat an extra amount of food, at a rate of 1250 kJ/d. We wanted to evaluate this advice and to assess how well-nourished women meet the energy demands of pregnancy. We took a series of measurements of a group of women before pregnancy and at two time points during pregnancy. We found that pregnant women can compensate for large increases in metabolism by minimizing the amount of fat deposited and possibly by reducing the amount of energy needed for activity. The different techniques that an individual woman will use cannot be predicted from prepregnant indexes. Also, circumstances differ; for example, one woman may have to perform more physical labor than another. Therefore, since individual women meet the energy demands of pregnancy in varying ways, it would not be appropriate t use a single recommendation for increased energy intake in all pregnant women. This information is useful in understanding and properly addressing the nutritional needs of women and their babies.

Technical Abstract: Background: Clinicians often recommend an additional energy intake of 1250 kJ/d to their pregnant patients. Previous studies have shown considerable variation in the metabolic response to pregnancy and thus in the additional energy required to support a pregnancy. Objective: The purpose of this study was to assess how well-nourished women nmeet the energy demands of pregnancy and to identify factors that predict an individual's metabolic response. Design: Resting metabolic rate (RMR), diet-induced thermogenesis (DIT), total energy expenditure (TEE), activity energy expenditure (AEE), energy intake (EI), and body fat mass (FM) were measured longitudinally in 10 women preconception; at 8-10, 24-26, and 34-36 wk of gestation; and 4-6 wk postpartum. Results: Compared with preconception values, individual RMRs increased from m456 to 3389 kJ/d by late pregnancy. DIT varied from -266 to 110 kJ/meal, TEE from -105 to 3421 kJ/d, AEE from -2301 to 2929 kJ/d, EI from -259 to 2176 kJ/d and FM from a 0.6-kg loss to a 10.6-kg gain. The only prepregnant factor that predicted FM gain was RMR (r=0.65, P < 0.05). Women with the largest cumulative increase in RMR deposited the least FM (r=-0.64, P < 0.05). Conclusions: Well-nourished women use different strategies to meet the energy demands of pregnancy, including reductions in DIT or AEE, increases in EI, and deposition of less FM than anticipated. The combination of strategies used by individual women is not wholly predictable from prepregnant indexes. The use of a single recommendation for increased energy intake in all pregnant women is not justified.