Oxorn-Foote HUMAN LABOR & BIRTH Sixth Edition Notice Medicine is an ever-changing science. As new research and clinical experience broaden our knowledge, changes in treatment and drug therapy are required. The authors and the publisher of this work have checked with sources believed to be re- liable in their efforts to provide information that is complete and generally in accord with the standards accepted at the time of publication. However, in view of the pos- sibility of human error or changes in medical sciences, neither the authors nor the publisher nor any other party who has been involved in the preparation or publica- tion of this work warrants that the information contained herein is in every respect accurate or complete, and they disclaim all responsibility for any errors or omissions or for the results obtained from use of the information contained in this work. Read- ers are encouraged to confirm the information contained herein with other sources. For example and in particular, readers are advised to check the product information sheet included in the package of each drug they plan to administer to be certain that the information contained in this work is accurate and that changes have not been made in the recommended dose or in the contraindications for administration. This recommendation is of particular importance in connection with new or infrequently used drugs. Oxorn-Foote HUMAN LABOR & BIRTH Sixth Edition Glenn D. Posner, MDcM, Med, FRcSc Associate Professor, The University of Ottawa Department of Obstetrics and Gynecology The Ottawa Hospital Ottawa, Ontario, Canada Jessica Dy, MD, MPH, FRcSc Assistant Professor, The University of Ottawa Department of Obstetrics and Gynecology The Ottawa Hospital Ottawa, Ontario, Canada amanDa Black, MD, MPH, FRcSc Associate Professor, The University of Ottawa Department of Obstetrics and Gynecology The Ottawa Hospital Division of Pediatric Gynecology, Children’s Hospital of Eastern Ontario Ottawa, Ontario, Canada Griffith D. Jones, MBBS, MRcoG, FRcSc Assistant Professor, The University of Ottawa Medical Director, Obstetrics & Gynecology Ultrasound Division of Maternal–Fetal Medicine Department of Obstetrics and Gynecology The Ottawa Hospital Ottawa, Ontario, Canada New York Chicago San Francisco Lisbon London Madrid Mexico City Milan New Delhi San Juan Seoul Singapore Sydney Toronto Copyright © 2013 by McGraw-Hill Education, LLC. All rights reserved. Except as permitted under the United States Copyright Act of 1976, no part of this publication may be reproduced or distributed in any form or by any means, or stored in a database or retrieval system, without the prior written permission of the publisher. ISBN: 978-0-07-178023-0 MHID: 0-07-178023-8 The material in this eBook also appears in the print version of this title: ISBN: 978-0-07-174028-9, MHID: 0-07-174028-7. All trademarks are trademarks of their respective owners. Rather than put a trademark symbol after every occurrence of a trademarked name, we use names in an editorial fashion only, and to the benefi t of the trademark owner, with no intention of infringement of the trademark. Where such designations appear in this book, they have been printed with initial caps. McGraw-Hill Education eBooks are available at special quantity discounts to use as premiums and sales promotions, or for use in corporate training programs. To contact a representative please e-mail us at