Hostname: page-component-7c8c6479df-8mjnm Total loading time: 0 Render date: 2024-03-26T13:06:30.588Z Has data issue: false hasContentIssue false

Energy requirements during pregnancy and lactation

Published online by Cambridge University Press:  02 January 2007

Nancy F Butte*
Affiliation:
USDA/ARS Children's Nutrition Research Center, Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, 1100 Bates Street, Houston, TX 77030, USA
Janet C King
Affiliation:
Children's Hospital Oakland Research Institute, 5700 Martin Luther King Jr Way, Oakland, CA 94609, USA
*
*Corresponding author: Email nbutte@bcm.tmc.edu
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.
Objective

To estimate the energy requirements of pregnant and lactating women consistent with optimal pregnancy outcome and adequate milk production.

Design

Total energy cost of pregnancy was estimated using the factorial approach from pregnancy-induced increments in basal metabolic rate measured by respiratory calorimetry or from increments in total energy expenditure measured by the doubly labelled water method, plus energy deposition attributed to protein and fat accretion during pregnancy.

Setting

Database on changes in basal metabolic rate and total energy expenditure during pregnancy, and increments in protein based on measurements of total body potassium, and fat derived from multi-compartment body composition models was compiled. Energy requirements during lactation were derived from rates of milk production, energy density of human milk, and energy mobilisation from tissues.

Subjects

Healthy pregnant and lactating women.

Results

The estimated total cost of pregnancy for women with a mean gestational weight gain of 12.0 kg, was 321 or 325 MJ, distributed as 375, 1200, 1950 kJ day-1, for the first, second and third trimesters, respectively. For exclusive breastfeeding, the energy cost of lactation was 2.62 MJ day-1 based on a mean milk production of 749 g day-1, energy density of milk of 2.8 kJ g-1, and energetic efficiency of 0.80. In well-nourished women, this may be subsidised by energy mobilisation from tissues on the order of 0.72 MJ day-1, resulting in a net increment of 1.9 MJ day-1 over non-pregnant, non-lactating energy requirements.

Conclusions

Recommendations for energy intake of pregnant and lactating women should be updated based on recently available data.

Type
Research Article
Copyright
Copyright © The Authors 2005

References

1WHO. Energy and Protein Requirements. Report of a Joint FAO/WHO/UNU Expert Consultation. Technical Report Series No. 724. Geneva: World Health Organization, 1985.Google Scholar
2WHO. Maternal Anthropometry and Pregnancy Outcomes – A WHO Collaborative Study. Bulletin of the World Health Organization 1995; 73: S1–69.Google Scholar
3WHO. Physical Status: The Use and Interpretation of Anthropometry. Geneva: WHO, 1995.Google Scholar
4Kelly, A, Kevany, J, de Onis, M, Shah, PM. A WHO collaborative study of maternal anthropometry and pregnancy outcomes. International Journal of Gynaecology and Obstetrics: the Official Organ of the International Federation of Gynaecology and Obstetrics 1996; 53: 219–33.CrossRefGoogle ScholarPubMed
5Martorell, R, Delgado, HL, Valverde, V, Klein, RE. Maternal stature, fertility and infant mortality. Human Biology; an International Record of Research 1981; 53: 303–12.Google ScholarPubMed
6Merchant, KM, Villar, J, Kestler, E. Maternal height and newborn size relative to risk of intrapartum caesarean delivery and perinatal distress. BJOG: an International Journal of Obstetrics and Gynaecology 2001; 108: 689–96.Google ScholarPubMed
7Pickett, KE, Abrams, B, Selvin, S. Maternal height, pregnancy weight gain, and birthweight. American Journal of Human Biology: the Official Journal of the Human Biology Council 2000; 12: 682–7.3.0.CO;2-X>CrossRefGoogle ScholarPubMed
8Institute of Medicine and Food and Nutrition Board. Nutrition During Pregnancy. Washington, DC: National Academy Press, 1990.Google Scholar
9Kleinman, J. Maternal Weight Gain During Pregnancy: Determinants and Consequences. Hyattsville, MD: National Center for Health Statistics, Public Health Service, US Department of Health and Human Services, 1990.Google Scholar
10Abrams, B, Altman, SL, Pickett, KE. Pregnancy weight gain: still controversial. American Journal of Clinical Nutrition 2000; 71: S1233–41.CrossRefGoogle ScholarPubMed
11Hytten, FE, Chamberlain, G. Clinical Physiology in Obstetrics. Oxford: Blackwell Scientific Publications, 1991.Google Scholar
12Blaxter, K. Energy Metabolism in Animals and Man. Cambridge: Cambridge University Press, 1989.Google Scholar
13Hytten, FE. Nutrition. In: Hytten, FE, Chamberlain, G, eds. Clinical Physiology in Obstetrics. Part 2. Nutrition and Metabolism. Oxford: Blackwell Scientific Publications, 1980; 163–92.Google Scholar
14MacGillivray, I, Buchanan, TJ. Total exchangeable sodium and potassium in non-pregnant women and in normal and pre-eclamptic pregnancy. Lancet 1958; 2: 1090–3.CrossRefGoogle Scholar
15King, JC, Calloway, DH, Margen, S. Nitrogen retention, total body 40K and weight gain in teenage pregnant girls. Journal of Nutrition 1973; 103: 772–85.CrossRefGoogle Scholar
16Emerson, K Jr, Poindexter, EL, Kothari, M. Changes in total body composition during normal and diabetic pregnancy. Relation to oxygen consumption. Obstetrics and Gynecology 1975; 45: 505–11.Google ScholarPubMed
17Pipe, NGJ, Smith, T, Halliday, D, Edmonds, CJ, Williams, C, Coltart, TM. Changes in fat, fat-free mass and body water in normal human pregnancy. British Journal of Obstetrics and Gynaecology 1979; 86: 929–40.CrossRefGoogle Scholar
18Forsum, E, Sadurskis, A, Wager, J. Resting metabolic rate and body composition of healthy Swedish women during pregnancy. American Journal of Clinical Nutrition 1988; 47: 942–7.CrossRefGoogle ScholarPubMed
19Butte, NF, Hopkinson, JM, Ellis, K, Wong, WW, Treuth, MS, Smith, EO. Composition of gestational weight gain impacts maternal fat retention and infant birth weight. American Journal of Obstetrics and Gynecology 2003; 189: 1423–32.CrossRefGoogle ScholarPubMed
20Spaaij, CJK. The efficiency of energy metabolism during pregnancy and lactation in well-nourished Dutch women. The Netherlands: University of Wageningen, 1993.Google Scholar
21Durnin, JVGA, McKillop, FM, Grant, S, Fitzgerald, G. Energy requirements of pregnancy in Scotland. Lancet 1987; 2: 897900.CrossRefGoogle ScholarPubMed
22van Raaij, JMA, Vermaat-Miedema, SH, Schonk, CM, Peek, MEM, Hautvast, JGAJ. Energy requirements of pregnancy in The Netherlands. Lancet 1987; ii: 953–5.CrossRefGoogle Scholar
23Thongprasert, K, Tanphaichitre, V, Valyasevi, A, Kittigool, J, Durnin, JV. Energy requirements of pregnancy in rural Thailand. Lancet 1987; 2: 1010–2.CrossRefGoogle ScholarPubMed
24Tuazon, MA, van Raaij, JM, Hautvast, JG, Barba, CV. Energy requirements of pregnancy in the Philippines. Lancet 1987; 2: 1129–31.CrossRefGoogle ScholarPubMed
25Barba, CVC. Progress Report on Study on Maternal Energy Requirements During Pregnancy and Lactation of Rural Philippine Women. Los Banos: Institute of Human Nutrition and Food, University of the Philippines, 1994.Google Scholar
26Lawrence, M, Coward, WA, Lawrence, F, Cole, TJ, Whitehead, RG. Fat gain during pregnancy in rural African women: the effect of season and dietary status. American Journal of Clinical Nutrition 1987; 45: 1442–50.CrossRefGoogle ScholarPubMed
27Hopkinson, JM, Butte, NF, Ellis, KJ, Wong, WW, Puyau, MR, Smith, EO. Body fat estimation in late pregnancy and early postpartum: comparison of two–, three–, and four–component models. American Journal of Clinical Nutrition 1997; 65: 432–8.CrossRefGoogle ScholarPubMed
28van Raaij, JMA, Peek, MEM, Vermaat–Miedema, SH, Schonk, CM, Hautvast, JGAJ. New equations for estimating body fat mass in pregnancy from body density or total body water. American Journal of Clinical Nutrition 1988; 48: 24–9.CrossRefGoogle ScholarPubMed
29Siri, WE. Body composition from fluid spaces and density: an analysis of methods. In: Broszek, J, Henschel, A, eds. Techniques for Measuring Body Composition. Washington, DC: National Academy of Science–National Research Council, 1961.Google Scholar
30Fuller, NJ, Jebb, SA, Laskey, MA, Coward, WA, Elia, M. Four-component model for the assessment of body composition in humans: comparison with alternative methods, and evaluation of the density and hydration of fat-free mass. Clinical Science 1992; 82: 687–93.CrossRefGoogle ScholarPubMed
31de Groot, LCPGM, Boekholt, HA, Spaaij, CJK, van Raaij, JMA, Drijvers, JJMM, van der Heijden, LJM, Hautvast, JGAJ. Energy balances of Dutch women before and during pregnancy: limited scope for metabolic adaptations in pregnancy. American Journal of Clinical Nutrition 1994; 59: 827–32.CrossRefGoogle ScholarPubMed
32Goldberg, GR, Prentice, AM, Coward, WA, Davies, HL, Murgatroyd, PR, Wensing, C, Black, AE, Harding, M, Sawyer, M. Longitudinal assessment of energy expenditure in pregnancy by the doubly labelled water method. American Journal of Clinical Nutrition 1993; 57: 494505.CrossRefGoogle Scholar
33Koop-Hoolihan, LE, Van Loan, MD, Wong, WW, King, JC. Fat mass deposition during pregnancy using a four-component model. Journal of Applied Physiology 1999; 87: 196202.CrossRefGoogle Scholar
34Butte, NF, Wong, WW, Treuth, MS, Ellis, K, Smith, EO. Energy requirements during pregnancy based on total energy expenditure and energy deposition. American Journal of Clinical Nutrition 2004; 79: 1078–87.CrossRefGoogle ScholarPubMed
35Kopp-Hoolihan, LE, Van Loan, MD, Wong, WW, King, JC. Longitudinal assessment of energy balance in well-nourished, pregnant women. American Journal of Clinical Nutrition 1999; 69: 697704.CrossRefGoogle ScholarPubMed
36Poppitt, SD, Prentice, AM, Jequier, E, Schutz, Y, Whitehead, RG. Evidence of energy sparing in Gambian women during pregnancy: a longitudinal study using whole-body calorimetry. American Journal of Clinical Nutrition 1993; 57: 353–64.CrossRefGoogle ScholarPubMed
37Prentice, AM, Spaaij, CJK, Goldberg, GR, Poppitt, SD, van Raaij, JMA, Totton, M, Swann, D, Black, AE. Energy requirements of pregnant and lactating women. European Journal of Clinical Nutrition 1996; 50: S82–111.Google ScholarPubMed
38Prentice, AM, Goldberg, GR, Davies, HL, Murgatroyd, PR, Scott, W. Energy-sparing adaptations in human pregnancy assessed by whole-body calorimetry. British Journal of Nutrition 1989; 62: 522.CrossRefGoogle ScholarPubMed
39Butte, NF, Hopkinson, JM, Mehta, N, Moon, JK, Smith, EO. Adjustments in energy expenditure and substrate utilization during late pregnancy and lactation. American Journal of Clinical Nutrition 1999; 69: 299307.CrossRefGoogle ScholarPubMed
40Heini, A, Schutz, Y, Jéquier, E. Twenty-four-hour energy expenditure in pregnant and nonpregnant Gambian women, measured in a whole-body indirect calorimeter. American Journal of Clinical Nutrition 1992; 55: 1078–85.CrossRefGoogle Scholar
41Goldberg, GR, Prentice, AM, Coward, WA, Davies, HL, Murgatroyd, PR, Sawyer, MB, Ashford, J, Black, AE. Longitudinal assessment of the components of energy balance in well-nourished lactating women. American Journal of Clinical Nutrition 1991; 54: 788–98.CrossRefGoogle ScholarPubMed
42Forsum, E, Kabir, N, Sadurskis, A, Westerterp, K. Total energy expenditure of healthy Swedish women during pregnancy and lactation. American Journal of Clinical Nutrition 1992; 56: 334–42.CrossRefGoogle ScholarPubMed
43Heini, A, Schutz, Y, Diaz, E, Prentice, AM, Whitehead, RG, Jequier, E. Free-living energy expenditure measured by two independent techniques in pregnant and nonpregnant Gambian women. American Journal of Physiology 1991; 261: E9–17.Google ScholarPubMed
44Singh, J, Prentice, AM, Diaz, E, Coward, WA, Ashford, J, Sawyer, M, Whitehead, RG. Energy expenditure of Gambian women during peak agricultural activity measured by the doubly-labelled water method. British Journal of Nutrition 1989; 62: 315–29.CrossRefGoogle ScholarPubMed
45Panter-Brick, C. Seasonality of energy expenditure during pregnancy and lactation for rural Napali women. American Journal of Clinical Nutrition 1993; 57: 620–8.CrossRefGoogle Scholar
46Dufour, DL, Reina, JC, Spurr, G. Energy intake and expenditure of free–living, pregnant Colombian women in an urban setting. American Journal of Clinical Nutrition 1999; 70: 269–76.CrossRefGoogle Scholar
47Durnin, JVGA. Energy metabolism in pregnancy. In: Cowett, R, eds. Principles of Perinatal-Neonatal Metabolism. New York: Springer, 1992, 228–36.Google Scholar
48Spaaij, CJK, van Raaij, JMA, van der Heijden, LJM, Schouten, FJM, Drijvers, JJMM, de Groot, LCPGM, Boekholt, HA, Hautvast, JGAJ. No substantial reduction of the thermic effect of a meal during pregnancy in well-nourished Dutch women. British Journal of Nutrition 1994; 71: 335–44.CrossRefGoogle ScholarPubMed
49Nagy, NE, King, JC. Postprandial energy expenditure and respiratory quotient during early and late pregnancy. American Journal of Clinical Nutrition 1984; 40: 1258–63.CrossRefGoogle ScholarPubMed
50Illingworth, PJ, Jung, RT, Howie, PW, Isles, TE. Reduction in postprandial energy expenditure during pregnancy. British Medical Journal 1987; 294: 1573–6.CrossRefGoogle ScholarPubMed
51Schutz, Y, Golay, A, Jéquier, E. 24 h energy expenditure (24-EE) in pregnant women with a standardized activity level. Experientia 1988; 44: A31.Google Scholar
52Contaldo, F, Scalfi, L, Coltorti, A, Di Palo, MR, Martinelli, P, Guerritore, T. Reduced regulatory thermogenesis in pregnant and ovariectomized women. International Journal for Vitamin and Nutrition Research. Internationale Zeitschrift fur Vitamin- und Ernahrungsforschung. Journal International de Vitaminologie et de Nutrition 1987; 57: 299304.Google ScholarPubMed
53Blackburn, MW, Calloway, DH. Energy expenditure of pregnant adolescents. Journal of the American Dietetic Association 1974; 65: 2430.CrossRefGoogle ScholarPubMed
54Blackburn, MW, Calloway, DH. Basal metabolic rate and work energy expenditure of mature, pregnant women. Journal of the American Dietetic Association 1976; 69: 24–8.CrossRefGoogle ScholarPubMed
55Seitchik, J. Total body water and total body density of pregnant women. Journal of Obstetrics and Gynaecology 1967; 29: 155–65.Google ScholarPubMed
56Edward, MJ, Metcalfe, J, Dunham, MJ, Maul, MS. Accelerated respiratory response to moderate exercise in late pregnancy. Respiration Physiology 1981; 45: 229–41.CrossRefGoogle Scholar
57Blackburn, MW, Calloway, DH. Heart rate and energy expenditure of pregnant and lactating women. American Journal of Clinical Nutrition 1985; 42: 1161–9.CrossRefGoogle ScholarPubMed
58Durnin, JVGA. Energy requirements of pregnancy. Diabetes 1991; 40: 152–6.CrossRefGoogle ScholarPubMed
59van Raaij, JMA, Schonk, CM, Vermaat-Miedema, SH, Peek, MEM, Hautvast, JGAJ. Energy cost of walking at a fixed pace and self-selected pace before, during and after pregnancy. American Journal of Clinical Nutrition 1990; 51: 158–61.CrossRefGoogle Scholar
60Schoeller, D. Limitations in the assessment of dietary energy intake by self-report. Metabolism Clinical and Experimental 1995; 44: 1822.CrossRefGoogle ScholarPubMed
61Lindsay, CA, Huston, L, Amini, SB, Catalano, PM. Longitudinal changes in the relationship between body mass index and percent body fat in pregnancy. Obstetrics and gynecology 1997; 89: 377–82.CrossRefGoogle ScholarPubMed
62Institute of Medicine. Nutrition Issues in Developing Countries. Washington, DC: National Academy Press, 1992.Google Scholar
63March of Dimes. Nutrition Today Matters Tomorrow – A Report From the March of Dimes Task Force on Nutrition and Optimal Human Development, 2002.Google Scholar
64Kumbi, S, Isehak, A. Obstetric outcome of teenage pregnancy in Northwestern Ethiopia. East African Medical Journal 1999; 76: 138–40.Google ScholarPubMed
65Gortzak-Uzan, L, Hallak, M, Press, F, Katz, M, Shoham-Vardi, I. Teenage pregnancy: risk factors for adverse perinatal outcome. Journal of Maternal-fetal Medicine 2001; 10: 393–7.CrossRefGoogle ScholarPubMed
66Larsson, J, Svanberg, L. Teenage deliveries in a Swedish population in the 1970's. Acta Obstetricia et Gynecologica Scandinavica 1983; 62: 467–72.CrossRefGoogle Scholar
67Bwibo, N. Birthweights of infants of teenage mothers in Nairobi. Acta Paediatrica Scandinavica Supplement 1985; 319: 8994.CrossRefGoogle ScholarPubMed
68Lao, T, Ho, L. The obstetric implications of teenage pregnancy. Human reproduction 1997; 12: 2303–5.CrossRefGoogle ScholarPubMed
69Jolly, M, Sebire, N, Harris, J, Robinson, S, Regan, L. Obstetric risks of pregnancy in women less than 18 years old. Obstetrics and Gynecology 2000; 96: 962–6.Google Scholar
70Prentice, A, Paul, A, Black, A, Cole, T, Whitehead, R. Cross-cultural differences in lactational performance. In: Hamosh, M, Goldman, AS, eds. Human Lactation 2: Maternal and Environmental Factors. New York: Plenum Press, 1986; 1344.CrossRefGoogle Scholar
71WHO Expert Consultation. Expert Consultation on the Optimal Duration of Exclusive Breastfeeding. Conclusions and Recommendations. Geneva, Switzerland: WHO, 2001.Google Scholar
72Brown, K, Dewey, KG, Allen, L. Complementary Feeding of Young Children in Developing Countries: a Review of Current Scientific Knowledge. Geneva: World Health Organization, 1998.Google Scholar
73Garza, C, Butte, NF. Energy concentration of human milk estimated from 24-hour pools and various abbreviated sampling schemes. Journal of Pediatric Gastroenterology and Nutrition 1986; 5: 943–8.Google Scholar
74Prentice, AM, Prentice, A. Energy costs of lactation. Annual Review of Nutrition 1988; 8: 6379.CrossRefGoogle ScholarPubMed
75Thompson, AM. The energy cost of human lactation. British Journal of Nutrition 1970; 24: 565–74.CrossRefGoogle Scholar
76Frigerio, C, Schutz, Y, Prentice, A, Whitehead, R, Jequier, E. Is human lactation a particularly efficient process?. European Journal of Clinical Nutrition 1991; 45: 459–62.Google Scholar
77Butte, NF, Wong, WW, Hopkinson, JM. Energy requirements of lactating women derived from doubly labelled water and milk energy output. Journal of Nutrition 2001; 131: 53–8.CrossRefGoogle ScholarPubMed
78Butte, NF, Barbosa, L, Villalpando, S, Wong, WW, Smith, EO. Total energy expenditure and physical activity level of lactating Mesoamerindians. Journal of Nutrition 1997; 127: 299305.Google ScholarPubMed
79Brent, NB, Redd, B, Dworetz, A, D'Amico, F, Greenberg, JJ. Breast-feeding in a low-income population. Archives of Pediatrics and Adolescent Medicine 1995; 149: 798803.CrossRefGoogle Scholar
80Lovelady, CA, Meredith, CN, McCrory, MA, Nommsen, LA, Joseph, LJ, Dewey, KG. Energy expenditure in lactating women: a comparison of doubly labelled water and heart-rate-monitoring methods. American Journal of Clinical Nutrition 1993; 57: 512–8.CrossRefGoogle ScholarPubMed
81Sadurskis, A, Kabir, N, Wager, J, Forsum, E. Energy metabolism, body composition, and milk production in healthy Swedish women during lactation. American Journal of Clinical Nutrition 1988; 48: 44–9.CrossRefGoogle ScholarPubMed
82Spaaij, CJK, van Raaij, JMA, de Groot, LCPGM, van derHeijden, LJM, Boekholt, HA, Hautvast, JGAJ. Effect of lactation on resting metabolic rate and on diet – and work-induced thermogenesis. American Journal of Clinical Nutrition 1994; 59: 42–7.CrossRefGoogle ScholarPubMed
83Schutz, Y, Lechtig, A, Bradfield, RB. Energy expenditures and food intakes of lactating women in Guatemala. American Journal of Clinical Nutrition 1980; 33: 892902.CrossRefGoogle ScholarPubMed
84Guillermo-Tuazon, MA, Barba, CVC, van Raaij, JMA, Hautvast, JGAJ. Energy intake, energy expenditure, and body composition of poor rural Philippine women throughout the first 6 mo of lactation. American Journal of Clinical Nutrition 1992; 56: 874–80.CrossRefGoogle ScholarPubMed
85Illingworth, PJ, Jung, RT, Howie, PW, Leslie, P, Isles, TE. Diminution in energy expenditure during lactation. British Medical Journal 1986; 292: 437–41.CrossRefGoogle ScholarPubMed
86Motil, KJ, Montandon, CM, Garza, C. Basal and postprandial metabolic rates in lactating and non-lactating women. American Journal of Clinical Nutrition 1990; 52: 610–5.CrossRefGoogle Scholar
87Frigerio, C, Schutz, Y, Whitehead, RG, Jéquier, E. Postprandial thermogenesis in lactating and non-lactating women from the Gambia. European Journal of Clinical Nutrition 1992; 46: 713.Google ScholarPubMed
88van Raaij, JMA, Schonk, CM, Vermaat-Miedema, SH, Pek, MEM, Hautvast, JGAJ. Energy cost of physical activity throughout pregnancy and the first year postpartum in Dutch women with sedentary lifestyles. American Journal of Clinical Nutrition 1990; 52: 234–9.CrossRefGoogle ScholarPubMed
89Butte, NF, Hopkinson, JM. Body composition changes during lactation are highly variable among women. Journal of Nutrition 1998; 128: S381–5.CrossRefGoogle ScholarPubMed
90Roberts, SB, Paul, AA, Cole, TJ, Whitehead, RG. Seasonal changes in activity, birth weight and lactational performance in rural Gambian women. Transactions of the Royal Society of Tropical Medicine and Hygiene 1982; 76: 668–78.CrossRefGoogle ScholarPubMed
91Allen, LH, Bakstrand, JR, Chavez, A, Pelto, GH. People Cannot Live by Tortillas Alone: The Result of the Mexico Nutrition CRSP. Washington: Final report to the US Agency for International Development, 1992.Google Scholar
92Black, AE, Wiles, SJ, Paul, AA. The nutrient intakes of pregnant and lactating mothers of good socio-economic status in Cambridge, UK: some implications for recommended daily allowances of minor nutrients. British Journal of Nutrition 1986; 56: 5972.CrossRefGoogle ScholarPubMed
93English, RM, Hitchcock, NE. Nutrient intakes during pregnancy, lactation and after the cessation of lactation in a group of Australian women. British Journal of Nutrition 1968; 22: 615–24.CrossRefGoogle Scholar
94Schofield, C, Wheeler, E, Stewart, J. The diets of pregnant and post-pregnant women in different social groups in London and Edinburgh: energy, protein, fat and fibre. British Journal of Nutrition 1987; 58: 369–81.CrossRefGoogle ScholarPubMed
95Whichelow, MJ. Success and failure of breast-feeding in relation to energy intake. Proceedings of the Nutrition Society 1975; 35: 62A–3A.Google Scholar
96Lederman, SA, Paxton, A, Heymsfield, SB, Wang, J, Thornton, J, Pierson, RN Jr. Body fat and water changes during pregnancy in women with different body weight and weight gain. Obstetrics and Gynecology 1997; 90: 483–8.CrossRefGoogle ScholarPubMed
97Sohlström, A, Forsum, E. Changes in total body fat during the human reproductive cycle as assessed by magnetic resonance imaging, body water dilution, and skinfold thickness: a comparison of methods. American Journal of Clinical Nutrition 1997; 66: 1315–22.CrossRefGoogle ScholarPubMed
98Durnin, JVGA, McKillop, FM, Grant, S, Fitzgerald, G. Energy requirements of pregnancy in Scotland. Lancet 1987; 2: 897900.CrossRefGoogle ScholarPubMed
99de Groot, LCPGM, Boekholt, HA, Spaaij, CJK, van Raaij, JMA, Drijvers, JJMM, van der Heijden, LJM, Hautvast, JGAJ. Energy balances of healthy Dutch women before and during pregnancy: limited scope for metabolic adaptations in pregnancy. American Journal of Clinical Nutrition 1994; 59: 827–32.CrossRefGoogle ScholarPubMed
100Lawrence, M, Whitehead, RG. Physical activity and total energy expenditure of child-bearing Gambian village women. European Journal of Clinical Nutrition 1988; 42: 145–60.Google ScholarPubMed
101Wood, CS, Isaacs, PC, Jensen, M, Hilton, HG. Exclusively breast-fed infants: growth and caloric intake. Pediatric nursing 1988; 14: 117–24.Google ScholarPubMed
102Butte, NF, Garza, C, Smith, EO, Nichols, BL. Human milk intake and growth of exclusively breast-fed infants. Journal of Pediatrics 1984; 104: 187–95.CrossRefGoogle ScholarPubMed
103Butte, NF, Wong, WW, Ferlic, L, Smith, EO. Energy expenditure and deposition of breast-fed and formula-fed infants during early infancy. Pediatric Research 1990; 28: 631–40.CrossRefGoogle ScholarPubMed
104Dewey, KG, Heinig, MJ, Nommsen, LA, Lonnerdal, B. Adequacy of energy intake among breast-fed infants in the DARLING study: relationships to growth velocity, morbidity, and activity levels. Journal of Pediatrics 1991; 119: 538–47.CrossRefGoogle ScholarPubMed
105Motil, KJ, Sheng, H-P, Montandon, CM, Wong, WW. Human milk protein does not limit growth of breast-fed infants. Journal of Pediatric Gastroenterology and Nutrition 1997; 24: 10–7.Google Scholar