WEIGHT GAIN DURING PREGNANCY
REEXAMINING THE GUIDELINES
Kathleen M. Rasmussen and Ann L. Yaktine, Editors
THE NATIONAL ACADEMIES PRESS
THE NATIONAL ACADEMIES PRESS
500 Fifth Street, N.W. Washington, DC 20001
NOTICE: The project that is the subject of this report was approved by the Governing Board of the National Research Council, whose members are drawn from the councils of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The members of the committee responsible for the report were chosen for their special competences and with regard for appropriate balance.
This study was supported by Contract No. HHSH250200446009I TO HHSH240G5806 between the National Academy of Sciences and U.S. Department of Health and Human Services Health Resources and Services Administration; Contract No. 200-2007-M-21619 between the National Academy of Sciences and Centers for Disease Control and Prevention Division of Nutrition, Physical Activity and Obesity; Contract No. N01-OD-4-2139 TO 192 between the National Academy of Sciences and National Institutes of Health Eunice Kennedy Shriver National Institute of Child Health and Human Development; Contract No. N01-OD-4-2139 TO 192 between the National Academy of Sciences and National Institutes of Health National Institute of Diabetes and Digestive and Kidney Diseases; Contract No. HHSP23300700522P between the National Academy of Sciences and U.S. Department of Health and Human Services Office on Women’s Health; Contract No. HHSP23320070071P between the National Academy of Sciences and U.S. Department of Health and Human Services Office of Disease Prevention and Health Promotion; and Contract No. 21-FY07-576 between the National Academy of Sciences and March of Dimes. Additional support came from U.S. Department of Health and Human Services Office of Minority Health and the National Minority AIDS Council. Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the organizations or agencies that provided support for this project.
Library of Congress Cataloging-in-Publication Data
Weight gain during pregnancy : reexamining the guidelines / Kathleen M. Rasmussen and Ann L. Yaktine, editors ; Committee to Reexamine IOM Pregnancy Weight Guidelines, Food and Nutrition Board and Board on Children, Youth, and Families.
p. ; cm.
Includes bibliographical references and index.
ISBN 978-0-309-13113-1 (hardback)
1. Pregnant women—Weight gain. I. Rasmussen, Kathleen M. II. Yaktine, Ann L. III. Institute of Medicine (U.S.). Committee to Reexamine IOM Pregnancy Weight Guidelines.
[DNLM: 1. Prenatal Care—United States. 2. Weight Gain—United States. 3. Practice Guidelines as Topic—United States. 4. Pregnancy—United States. 5. Pregnancy Complications—prevention & control—United States. WQ 175 W419 2009]
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Suggested citation: IOM (Institute of Medicine) and NRC (National Research Council). 2009. Weight Gain During Pregnancy: Reexamining the Guidelines. Washington, DC: The National Academies Press.
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COMMITTEE TO REEXAMINE IOM PREGNANCY WEIGHT GUIDELINES
KATHLEEN M. RASMUSSEN (Chair), Professor of Nutrition,
Division of Nutritional Sciences, Cornell University, Ithaca, NY
BARBARA ABRAMS, Professor,
School of Public Health, University of California–Berkeley
LISA M. BODNAR, Assistant Professor,
Department of Epidemiology, University of Pittsburgh, PA
CLAUDE BOUCHARD, Executive Director and George A. Bray Chair in Nutrition,
Pennington Biomedical Research Center, Baton Rouge, LA
NANCY BUTTE, Professor of Pediatrics,
Baylor College of Medicine, Houston, TX
PATRICK M. CATALANO, Chair,
Department of Obstetrics and Gynecology, Case Western Reserve University, Cleveland, OH
MATTHEW W. GILLMAN, Professor,
Department of Ambulatory Care and Prevention, Harvard Medical School and Harvard Pilgrim Health Care, Boston, MA
FERNANDO A. GUERRA, Director of Health,
San Antonio Metropolitan Health District, TX
PAULA A. JOHNSON, Executive Director,
Connors Center for Women’s Health and Gender Biology, Chief, Division of Women’s Health, Brigham and Women’s Hospital, Boston, MA
MICHAEL C. LU, Associate Professor of Obstetrics,
Gynecology, and Public Health, Schools of Medicine and Public Health, University of California–Los Angeles
ELIZABETH R. McANARNEY, Professor and Chair Emerita,
Department of Pediatrics, School of Medicine and Dentistry, University of Rochester, NY
RAFAEL PÉREZ-ESCAMILLA, Professor of Nutritional Sciences & Public Health, Director,
NIH EXPORT Center for Eliminating Health Disparities Among Latinos, University of Connecticut, Storrs
DAVID A. SAVITZ, Charles W. Bluhdorn Professor of Community & Preventive Medicine, Director,
Epidemiology, Biostatistics, and Disease Prevention Institute, Mount Sinai School of Medicine, New York, NY
ANNA MARIA SIEGA-RIZ, Associate Professor,
Department of Epidemiology, School of Public Health, University of North Carolina–Chapel Hill
ANN L. YAKTINE, Senior Program Officer
HEATHER B. DEL VALLE, Research Associate
This report has been reviewed in draft form by individuals chosen for their diverse perspectives and technical expertise, in accordance with procedures approved by the National Research Council’s (NRC’s) Report Review Committee. The purpose of this independent review is to provide candid and critical comments that will assist the institution in making its published report as sound as possible and to ensure that the report meets institutional standards for objectivity, evidence, and responsiveness to the study charge. The review comments and draft manuscript remain confidential to protect the integrity of the deliberative process. We wish to thank the following individuals for their review of this report:
Haywood Brown, Department of Obstetrics and Gynecology, Duke University Medical Center, Durham, NC
Cutberto Garza, Boston College, MA
Susan Gennaro, William F. Connell School of Nursing, Boston College, MA
William Goodnight, Department of Obstetrics and Gynecology, Division of Maternal-Fetal Medicine, University of North Carolina–Chapel Hill School of Medicine
Erica P. Gunderson, Division of Research, Kaiser Permanente, Oakland, CA
Maxine Hayes, Department of Health, State of Washington, Tumwater
Lorraine V. Klerman, The Heller School for Social Policy and Management, Brandeis University, Waltham, MA
Kristine G. Koski, School of Dietetics and Human Nutrition, McGill University, Ste. Anne de Bellevue, Quebec, Canada
Charles Lockwood, Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale University School of Medicine, New Haven, CT
Dawn Misra, Division of Epidemiology and Biostatistics, Department of Family Medicine and Public Health Sciences, Wayne State University School of Medicine, Detroit, MI
Jose M. Ordovas, Nutrition and Genomics Laboratory, Jean Mayer USDA Human Nutrition Research Center on Aging, Tufts University, Boston, MA
Roy M. Pitkin, University of California–Los Angeles (Professor Emeritus)
David Rush, Friedman School of Nutrition Science and Policy (Professor Emeritus), Tufts University, Boston, MA
Jeanette South-Paul, Department of Family Medicine, University of Pittsburgh, PA
Although the reviewers listed above have provided many constructive comments and suggestions, they were not asked to endorse the conclusions or recommendations nor did they see the final draft of the report before its release. The review of this report was overseen by Neal A. Vanselow, Tulane University, Professor Emeritus and Nancy E. Adler, Departments of Psychiatry and Pediatrics and Center for Health and Community, University of California–San Francisco.
Appointed by the NRC and Institute of Medicine, they were responsible for making certain that an independent examination of this report was carried out in accordance with institutional procedures and that all review comments were carefully considered. Responsibility for the final content of this report rests entirely with the authoring committee and the institution.
In the last century, many answers have been given by health professionals to the question “how much weight should I gain while I am pregnant?” In the early 1900s, the answer was often only 15-20 pounds. Between 1970 and 1990, the guideline for weight gain during pregnancy was higher, 20-25 pounds, and in 1990, with the publication of Nutrition During Pregnancy, it went higher still for some groups of women. This most recent guideline reflected new knowledge about the importance of maternal body fatness before conception, as measured by body mass index, for the outcome of pregnancy. It had become clear that heavier women could gain less weight and still deliver an infant of good size. Since that time, the obesity epidemic has not spared women of reproductive age. In our population today, more women of reproductive age are severely obese (obesity class III; 8 percent) than are underweight (3 percent), and their short- and long-term health has become a concern in addition to the size of the infant at birth. Clearly the time had come to reexamine the guidelines for weight gain during pregnancy.
To prepare for this possibility, the National Research Council and the Institute of Medicine held a workshop in 2006 to evaluate the availability of data that could be used to reexamine the current guidelines. Based on the outcome of this workshop, numerous federal agencies (U.S. Department of Health and Human Services Health Resources and Services Administration; Centers for Disease Control and Prevention Division of Nutrition and Physical Activity and Obesity; National Institutes of Health Eunice Kennedy Shriver National Institute of Child Health and Human
Development; National Institutes of Health National Institute of Diabetes and Digestive and Kidney Diseases; U.S. Department of Health and Human Services Office on Women’s Health; U.S. Department of Health and Human Services Office of Disease Prevention and Health Promotion; March of Dimes; with additional support from U.S. Department of Health and Human Services Office of Minority Health and the National Minority AIDS Council) agreed to sponsor the work of this committee.
The committee was asked to review the determinants and a wide range of short- and long-term consequences of variation in weight gain during pregnancy for both the mother and her infant. Based on the outcome of this review, the committee was asked to recommend revisions to the current guidelines if this was deemed to be necessary. In addition, the committee was asked to consider the approaches that might be necessary to promote appropriate weight gain and to identify gaps in knowledge and make recommendations about priorities for future research.
Although many studies relevant to the committee’s charge have been published since 1990 and the Agency for Healthcare Research and Quality (AHRQ) completed its report Outcomes of Maternal Weight Gain while the committee was gathering data, many gaps in knowledge remained. To address this problem, the committee held a public session with project sponsors, and two workshops. We are grateful to those who participated in these sessions for sharing their experience and wisdom. We are also grateful to a number of individuals who supplied data to the committee: Raul Artal, Amy Branum, Marie Cedergren, Aimin Chen, K.S. Joseph, Sharon Kirmeyer, Joyce Martin, Alan Ryan, and Andrea Sharma, with special thanks to Patricia Dietz. The committee also commissioned additional analyses of data from both Denmark and the United States. We thank our consultants, Amy Herring, Ellen Aagaard Nohr, and Cheryl Stein for these analyses and for their contributions to the committee’s work. The committee also felt that it was important to understand what would be involved in analyzing the trade-off between mother and infant in risk of adverse outcomes of variation in weight gain during pregnancy. To accomplish this, we commissioned such an analysis based on the data at hand. We thank our consultant, James Hammitt, for conducting these analyses and for his contribution to the committee’s work.
The committee’s 14 members gave freely of their expertise and volunteered their time and energy in all aspects of the preparation of this report, from developing its intellectual framework, writing the text, and deliberating about the recommendations and conclusions of the report. Their efforts merit our sincere gratitude.
The committee received excellent staff support from Ann Yaktine, Study Director, Heather Del Valle, Research Associate, and Jennifer Datiles, Senior Program Assistant. Their effort on our behalf is sincerely appreci-
ated. We also thank Leslie Pray for technical editing and Florence Poillon for copyediting. Both the Director of the Food and Nutrition Board, Linda Meyers, and the Director of the Board on Children, Youth, and Families, Rosemary Chalk, contributed their wisdom and support to this effort, and we thank them for it.
Kathleen M. Rasmussen, Chair
Committee to Reexamine IOM Pregnancy Weight Guidelines