HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Purchase Article View Shopping Cart Alert me when this article is cited Alert me if a correction is posted Citation Map Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Lof, M. Articles by Forsum, E. Search for Related Content PubMed PubMed Citation Articles by Lof, M. Articles by Forsum, E. Agricola Articles by Lof, M. Articles by Forsum, E.

Changes in basal metabolic rate during pregnancy in relation to changes in body weight and composition, cardiac output, insulin-like growth factor I, and thyroid hormones and in relation to fetal growth^1,2,3

¹ From the Division of Nutrition, Department of Biomedicine and Surgery (ML, HO, AS, and EF), and the Division of Clinical Physiology, Department of Medicine and Care (BJ-S), University of Linkoping, Linkoping, Sweden, and the Lust och Hälsa (Pleasure and Health) Clinic, Linkoping, Sweden (KB).

Background: The total energy cost of pregnancy is largely due to an elevated basal metabolic rate (BMR). Large variations in the BMR response to pregnancy have been reported, but the factors associated with this variability are incompletely known.

Objective: The objective was to identify factors associated with variability in the BMR response to pregnancy.

Design: In 22 healthy women, BMR, body weight (BW), total body fat (TBF), fat-free mass (FFM), circulatory variables, serum concentrations of insulin-like growth factor I (IGF-I), and thyroid hormones were measured before pregnancy and in gestational weeks 14 and 32. BMR and BW were also measured in gestational weeks 8, 20, and 35. Fetal weight was estimated in gestational week 31.

Results: In gestational week 14, the increase in BMR correlated significantly with the corresponding increase in BW and with the prepregnancy percentage of TBF. Together these variables explained 40% of the variability in the BMR response. In gestational week 32, the increase in BMR correlated significantly with the corresponding changes in BW, TBF, FFM, IGF-I, cardiac output, and free triiodothyronine. The increase in BW in combination with fetal weight or with the elevated concentration of IGF-I in serum explained 60% of the variability in the increase in BMR.

Conclusions: Weight gain and the prepregnancy percentage of TBF—ie, factors related to the maternal nutritional situation—are important factors with regard to the variability in the BMR response to pregnancy. Thus, it is important to consider the nutritional situation before and during gestation when assessing pregnancy energy requirements.

Key Words: Basal metabolic rate • cardiac output • body composition • free triiodothyronine • insulin-like growth factor I • pregnancy

This article has been cited by other articles:

				S Kechagias, A Ernersson, O Dahlqvist, P Lundberg, T Lindstrom, F H Nystrom, and for the Fast Food Study Group Fast-food-based hyper-alimentation can induce rapid and profound elevation of serum alanine aminotransferase in healthy subjects Gut, May 1, 2008; 57(5): 649 - 654. [Abstract] [Full Text] [PDF]

				K. O O'Brien, C. M Donangelo, C. L V. Zapata, S. A Abrams, E M. Spencer, and J. C King Bone calcium turnover during pregnancy and lactation in women with low calcium diets is associated with calcium intake and circulating insulin-like growth factor 1 concentrations Am. J. Clinical Nutrition, February 1, 2006; 83(2): 317 - 323. [Abstract] [Full Text] [PDF]