Edited by

isbn 978-0-4709-6286-2

Supporting a Physiologic Approach to Pregnancy and BirthA Practical Guide

Melissa D. Avery

9 780470 962862

Supporting a Physiologic Approach to Pregnancy and B

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Supporting a Physiologic Approach to Pregnancy and Birth: A Practical Guide provides an overview of current evidence and a range of practical suggestions to promote physiologic birth within the United States healthcare system. Presenting the latest evidence available on practical approaches and minimal interventions, this book looks into clinic exam rooms and hospital labor units to investigate the possibilities for improving the pregnancy and labor experience. Contributors discuss recent research and other published information and present a range of ideas, tools, and solutions for maternity care clinicians, including midwives, nurses, physicians, and other members of the perinatal team.

Key FeAtures

Reviews the normal physiologic changes of pregnancy, labor, and birth and discusses care strategies during pregnancy and labor to support normal birth

Includes focus on broader care and education systems and how maternity care providers can work together to provide seamless quality care and effect solutions and policy changes

Explores in-hospital and out-of-hospital care methods Coverage includes physiology and supportive approach methods; interventions

such as touch therapies, water immersion, and acupuncture; and organizational approaches, including the current status of policies and recommendations for change

An invaluable resource, Supporting a Physiologic Approach to Pregnancy and Birth is a must-have practical guide for those involved in all aspects of pregnancy and birth.

the eDitorMelissa D. Avery, PhD, CNM, FACNM, FAAN, is Professor, Chair of the Child and Family Health Cooperative Unit, and directs the midwifery program at the University of Minnesota’s School of Nursing. She is the past president of the American College of Nursing Midwives. Dr. Avery has authored numerous articles and is nationally known for her research in midwifery and women’s health.

relAteD titles:The Labor Progress Handbook: Early Interventions to Prevent and Treat Dystocia, Third EditionBy Penny Simkin and Ruth AnchetaISBN: 9781444337716

Essential Midwifery Practice: Expertise, Leadership and Collaborative WorkingEdited by Soo Downe, Sheena Byrom and Louise SimpsonISBN: 9781405184311

Journal of Midwifery and Women’s HealthEdited by Frances E. LikisISSN: 1526-9523 (print) or 1542-2011 (online)

avery_9780470962862_cover.indd 1 3/18/13 9:34 AM

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Supporting a Physiologic Approach to Pregnancy and Birth

The optimal role of the attendant—whether physician or midwife—is to be vigilant

without being meddlesome.

R. A. Rosenblatt, MD

Supporting a Physiologic Approach to Pregnancy and BirthA Practical Guide

Edited by

Melissa D. Avery, PhD, CNM, FACNM, FAANProfessorChair, Child and Family Health Co-operativeUniversity of Minnesota, School of NursingMinneapolis, Minnesota

A John Wiley & Sons, Inc., Publication

This edition first published 2013 © 2013 by John Wiley & Sons, Inc

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Cover design by Matt Kuhns

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1 2013

Dedication

To the women—for allowing us the privilege of being present with them during

their special time.

And to my husband—Randy Schnoes—who is always there for me.

Contents

Contributors ixForeword by Holly Powell Kennedy xiAcknowledgments xiii

Section 1 Understanding a physiologic approach 1

1 The case for a physiologic approach to birth: An overview 3Melissa D. Avery

2 The physiology of pregnancy, labor, and birth 13Cindy M. Anderson

3 A supportive approach to prenatal care 29 Carrie E. Neerland

4 Supporting a physiologic approach to labor and birth 49 Lisa Kane Low and Rebeca Barroso

Section 2 Interventions and approaches 77

5 Promoting comfort: A conceptual approach 79 Kerri D. Schuiling

6 Continuous labor support 91 Carrie E. Neerland

7 Techniques to promote relaxation in labor 105 Kathryn Leggitt

8 Touch therapies in pregnancy and childbirth 119 Deborah Ringdahl

9 Water immersion for labor and birth 157 Michelle R. Collins and Dawn M. Dahlgren-Roemmich

10 Aromatherapy in pregnancy and childbirth 173Linda L. Halcón

11 Acupressure and acupuncture in pregnancy and childbirth 197 Katie Moriarty and Kennedy Sharp

viii Contents

Section 3 organizational approaches to supporting physiologic pregnancy and birth 227

12 Rethinking care on the hospital labor unit 229 Emily Higdon, Rachel Woodard, Kristin Rood and Heidi Jean Bernard

13 Out-of-hospital birth 251Marsha E. Jackson and Alice Bailes

14 Educating health professionals for collaborative practice in support of normal birth 275Melissa D. Avery, John C. Jennings and Michelle L. O’Brien

15 Women’s health and maternity care policies: Current status and recommendations for change 301Heather M. Bradford

Resources for physiologic pregnancy and childbirth 331Index 335

Contributors

Cindy M. Anderson, PhD, RN, WHNP-BC, FAANAssociate ProfessorDepartment of NursingCollege of Nursing and Professional DisciplinesUniversity of North DakotaGrand Forks, North Dakota

Melissa D. Avery, PhD, CNM, FACNM, FAANProfessorChair, Child and Family Health Co-operative UnitDirector, Nurse-Midwifery ProgramSchool of NursingUniversity of MinnesotaMinneapolis, Minnesota

Alice Bailes, CNM, MSN, FACNMCo-FounderBirth Care and Women’s HealthAlexandria, Virginia

Rebeca Barroso, DNP, CNMFaculty, Frontier Nursing UniversityStaff Nurse-MidwifeHealthEast Nurse-MidwivesSt. Paul, Minnesota

Heidi Jean Bernard, RN, ADNStaff NurseDepartment of Labor and DeliveryUniversity of Iowa Hospitals and ClinicsIowa City, Iowa

Heather M. Bradford, MSN, CNM, ARNP, FACNMCertified Nurse-MidwifeEvergreen Health Midwifery CareKirkland, WashingtonAffiliate FacultyDepartment of Family and Child NursingUniversity of WashingtonSeattle, Washington

Michelle R. Collins, PhD, CNMAssociate Professor of NursingDirector, Nurse-Midwifery ProgramVanderbilt University School of NursingNashville, Tennessee

Dawn M. Dahlgren-Roemmich, MS, CNMCertified Nurse-MidwifeJordan, Minnesota

Linda L. Halcón, PhD, MPH, RNAssociate ProfessorSchool of NursingUniversity of MinnesotaMinneapolis, Minnesota

Emily Higdon, RN, MSNPhD Student and Jonas ScholarStaff NurseDepartment of Labor and DeliveryUniversity of Iowa Hospitals and ClinicsIowa City, Iowa

x Contributors

Marsha E. Jackson, CNM, MSN, FACNMDirector and Co-FounderBirth Care and Women’s HealthAlexandria, Virginia

John C. Jennings, MDProfessor of Obstetrics and GynecologyTexas Tech University Health SciencesOdessa, Texas

Kathryn Leggitt, MS, CNMCertified Nurse-MidwifeHennepin County Medical CenterMinneapolis, Minnesota

Lisa Kane Low, PhD, CNM, FACNMAssistant Professor and Director Nurse-Midwifery Education ProgramSchool of Nursing and Women’s Studies DepartmentUniversity of MichiganAnn Arbor, Michigan

Katie Moriarty, PhD, CNM, CAFCI, RNClinical Assistant Professor Associate Director Nurse-Midwifery Education ProgramSchool of NursingUniversity of MichiganAnn Arbor, MichiganCertified Acupuncture Foundation of Canada Institute

Carrie E. Neerland, MS, CNMCertified Nurse-MidwifeWomen’s Health SpecialistsUniversity of Minnesota PhysiciansAdjunct FacultyUniversity of Minnesota School of NursingUniversity of Minnesota Medical SchoolMinneapolis, Minnesota

Michelle L. o’Brien, MD, MPH, IBCLCAdjunct FacultyAssistant ProfessorDepartment of Family Medicine and Community HealthUniversity of Minnesota Medical SchoolMinneapolis, Minnesota

Deborah Ringdahl, DNP, RN, CNMReiki MasterClinical Assistant ProfessorSchool of NursingUniversity of MinnesotaMinneapolis, Minnesota

Kristin Rood, RNMaternal and Infant Staff NurseChildren and Women’s Services DivisionUniversity of Iowa Hospitals and ClinicsIowa City, Iowa

Kennedy SharpLicensed AcupuncturistMasters in Oriental MedicineNCCAOM Certifiedsharpacupuncture.comMinneapolis, Minnesota

Kerri D. Schuiling, PhD, CNM, FACNM, FAANDeanSchool of NursingOakland UniversityRochester, Michigan

Rachel Woodard, RN, BSN, RNC-oBObstetrical Nurse Specialist Staff Nurse Labor and DeliveryDepartments of Pediatrics and NursingUniversity of Iowa Hospitals and ClinicsIowa City, Iowa

Foreword

Birth is an event that carries our universe into the future. Each pregnancy and birth holds the promise of fresh life, renewed faith in our survival, and awe at the magnificence of human reproduction and the power of woman. Every birth is unique and every birth changes the person fortunate enough to witness the emergence of a new life.

Melissa Avery has brought together midwives, nurses, physicians, and other health practitioners in a collective, in-depth discussion of how to support a woman’s physiologic capacity to carry and birth her child. This long overdue book is founded on the premise that pregnancy and birth are normal physiologic processes. It takes a direction often missing in traditional texts—that birth is more than simple mechanical, physical processes that can be inherently controlled. Rather, it acknowledges that although there is much we fully understand, there is still much to be learned. Thus, she and her colleagues have expertly woven current scientific evidence and theory with practical clinical expertise for helping women and their families during this life-producing and life-changing event.

The first section grounds the reader in a woman’s physiology during pregnancy and birth. Avery starts the section off with a “real-life” scenario that clinicians who attend birth are often faced with each day. This is followed by an exquisite description of the physiologic intricacies of pregnancy and parturition that leaves us breathless in its detail and design and sets the stage for understanding how it all works. Prenatal care is empha-sized as the place to work with the woman to establish her confidence in her body and its capabilities. The section closes with a stunning overview of how to keep the woman and her needs central during childbirth. The authors review the evidence on routine maternity care practices that can disrupt normal labor and birth and describe approaches to care that provide step-by-step support of a woman’s physiology. Taken together, these four chap-ters provide the essential elements of the book and lay the underpinning for the following sections, which explore specific techniques and policy.

The second section provides an overview of specific strategies in caring for childbearing women. Different theories and evidence for care strategies are presented, always return-ing to why and how they support normal physiologic birth. The section begins with an introduction to the theories of “comfort,” helping the reader understand how to meet each woman at the intersection of her life and her perception of pain and discomfort. The com-plexity of labor pain is disentangled through creative descriptions of pain modulation through the release of naturally occurring neuropeptides. The theoretical basis of comfort is extended by presence—the act by which the labor attendant creates a space in which the woman feels safe and thus her body’s physiology is supported to do the work of labor. Techniques of relaxation, healing touch, therapeutic use of water, aromatherapy, and

xii Foreword

acupressure/acupuncture round out the section. Each of the topics is carefully reviewed for current evidence and practical application. The end result of this portion of the book reveals the art and healing science of supporting physiologic birth.

The final section provides a welcome and practical discussion of the realities of change in childbearing care. Since childbirth moved into the hospital it has been regimented to institutional routines not always rooted in evidence. Although these routines were established in good faith and believed to be best for the mother and infant, that was not always the case. Over time routines became so conventional that changing them seemed insurmountable. The section begins by helping us rethink how care is provided in the hospital, where most women in the United States give birth. The challenges of creating a safe environment for the laboring woman within an institutional setting are creatively presented through case studies, principles from major advocacy organizations, and sys-tematically decreasing the use of routine interventions. Complementary to the chapter on hospital birth is a thoughtful presentation on out-of-hospital birth. Both chapters discuss the essential desire of women to be respected for their needs during labor and birth and the right to make decisions about where and how they birth. The authors challenge the idea that medicine is the final word in health care and place the woman at the center of care and as the director. They propose that this change of roles might actually enhance the woman’ s physiologic ability to birth. These are hefty sea changes in how we think about the roles of providers and the women for whom they care. Avery, Jennings, and O’ Brien emphasize the need for careful nurturing of the professions’ young through interdisci-plinary education in order to bring these changes about. By exploring issues together during the formative years of their professional identities, nurses, midwives, and physi-cians can learn together how to best work “with woman” during this profound moment of her life. The book closes by describing the need for policy to undergird the changes needed to best support women—through legislation, regulation, and institutional transformation.

If every clinician and institution that provides care to childbearing women instituted the recommendations in Supporting a Physiologic Approach to Pregnancy and Birth, we could truly see change in how women birth in the United States—and I believe improved outcomes. Perhaps the most important message in this book is the blending of our under-standing of human birth physiology with human caring. In Proust Was a Neuroscientist (Houghton Mifflin, 2007), Jonah Lehrer explored the relationship of artists with concepts in neuroscience, noting, “scientists describe our brain in terms of its physical details . . . what science forgets is that this isn’t how we experience the world” (p. x)—artists help us to understand how the world is perceived and lived. Avery and her colleagues help us understand both the science and the art of supporting women’ s physiology, how that can actually make birth safer, and how artful presence and caring approaches enhance the woman’ s experience and create a powerful mother and healthy child and family in the process. This book is a passage to the future in childbearing care.

Holly Powell Kennedy, PhD, CNM, FACNM, FAANHelen Varney Professor of Midwifery

Yale UniversityJanuary 1, 2013

Acknowledgments

This book would not have been possible without the dedication and hard work of each and every chapter author. Thank you so much for your contributions in providing the background information and practical advice to help maternity care clinicians in their efforts to promote a physiologic approach to pregnancy and childbirth. We have included the physiologic underpinnings, the normal aspects of pregnancy and labor care, multiple integrative therapies, and a focus on the care system including interprofessional education and policy. A special thank you to Deborah Ringdahl, DNP, RN, CNM. In addition to writing a wonderful chapter on touch therapies in pregnancy, her review of multiple chap-ters and advice on other aspects of the book were immensely helpful. Thank you to Lisa Summers, DrPH, CNM, FACNM, and Joanna King, JD, for their valuable contributions to the policy chapter.

Chapters on acupuncture and acupressure and touch therapies include photographs providing illustrations of the techniques described in the text. We thank Melissa Jackson, Aimee Flood, Beth Kuzma, and Lily Crutchfield for serving as models and helping bring the techniques to life. My research assistant, Colleen Quesnell, reviewed many sections and helped with so many other necessary details that are not evident in the final polished product. A special thanks to Kathe Grooms for expert advice along the way.

For more than three decades as a nurse and midwife, I have had the privilege of working with so many nurses, physicians, midwives, and others that have influenced my day-to-day work as well as broader career trajectory. The faculty and staff at the University of Minnesota, School of Nursing, and the students I have had the pleasure of teaching over the years deserve special thanks for their ongoing support.

Finally, my deepest gratitude to my daughter, Helen Avery Schnoes. Her helpful sug-gestions as a talented writer and her encouragement were invaluable all along the journey.

Understanding a physiologic approach

Section 1

Supporting a Physiologic Approach to Pregnancy and Birth: A Practical Guide, First Edition. Edited by Melissa D. Avery. © 2013 John Wiley & Sons, Inc. Published 2013 by John Wiley & Sons, Inc.

The case for a physiologic approach to birth: An overviewMelissa D. Avery

Childbirth is normal until proven otherwise. Peggy Vincent

Picture yourself at a neighborhood clinic on a typical weekday. You are conducting a health care visit with a woman as her prenatal care provider; she is 32 weeks pregnant. You ask how she has been feeling—she is fine. Her fundal height is 33 cm, the baby feels vertex, fetal heart tones are 134 beats per minute, a 2-pound weight gain since her last visit. No, she has not experienced any bleeding or headaches, no contractions. Yes, she started prenatal classes this week and the instructor reviewed the signs of early labor. Transition to the hospital. You’re the nurse admitting a woman in labor to the birthing room with the bed centrally located, the fetal monitor in an attractive wood cabinet next to the bed. You ask when her contractions began, the current frequency and duration, and if her baby has been moving. Her membranes are intact, vital signs are normal, fetal heart rate 148. While you turn down the bedcovers, she changes into a hospital gown and asks if water birth is possible; she read about it on a pregnancy website and thought it might be a nice option.

On the face of it, the daily experiences of many maternity care clinicians and the women we care for seem pretty normal, routine, and positive to a degree. We talk about pregnancy as a normal life process, yet women enter our care system where problems are anticipated rather than emphasizing the normalcy of pregnancy. The number and frequency of technological interventions continue to increase while the outcomes of care have worsened, with some recent abatement. Substantial national resources are spent on what is supposed to be a normal process. From the clinic to the hospital, how do we as nurses, midwives, and physicians provide a safe and high-quality experience for the women we care for during pregnancy and birth? How are we helping women plan for and achieve their goals and desires for their birth experiences?

Cesarean section has become the most common operating room procedure in America [1]. The U.S. cesarean section rate is nearly 33%, appearing to at least stabilize in 2010 and 2011 after rising by 60% from 1996 to 2009 [2,3]. The Healthy People 2020 goal is

Chapter 1

4 Supporting a Physiologic Approach to Pregnancy and Birth

a moderate 10% reduction in cesarean births to low-risk women (term, singleton, vertex) from a baseline of 26.5% in 2007 to 23.9% by 2020, as well as a 10% increase in vaginal births among women with a previous cesarean [4]. At the same time, infant mortality, a measure used worldwide to reflect care to mothers and families, is 6.05 deaths in the first year of life per 1,000 live births [5]. This is higher than all but three member countries of the Organisation for Economic Co-operation and Development (OECD), an organization of primarily developed countries including Europe, the United States, Canada, and others [6]. Infant mortality in the United States has declined from 6.71 per 1,000 live births in 2006 after remaining stable from 2000 to 2005 [7]. An 8% decline in premature births occurred from 12.80% in 2006 to 11.72% in 2011 [3], along with increased efforts at preventing early elective births such as the March of Dimes and the California Maternal Quality Care Collaborative [8,9]. Maternal mortality was 12.7 per 100,000 live births in 2007 [10], a number that may be increasing [11], with the U.S. rate behind forty-nine other developed nations in 2010 [12]. (See summary data in Table 1.1.)

Not readily apparent in these statistics are significant racial disparities. For example, infant mortality among African American women was 11.42 per 1,000 live births, 2.2 times greater than the 5.11 for White women [5]. Maternal mortality was approximately 3 times higher for African American women compared to White women [10,11]. These disparities are inexcusable in a country with such vast resources; we must reverse these trends by assuring access to continuous high-quality health care [13]. Returning to a more normal or physiologic approach to maternity care including access to comprehensive continuous care to all women in the United States is one step in that direction.

Spending and doing too much

Nearly 99% of U.S. births occur in hospitals [2], thus “liveborn infant” and “pregnancy and childbirth” are among the most common reasons for hospitalization [1], accounting for nearly a quarter of hospital discharges in 2008, and over $98 billion in hospital charges (amount hospitals bill for a stay). Medicaid payment covers the cost of care for over 40% of pregnancies and births [14]. Of “pregnancy and childbirth” and “liveborn infant” hospitalizations in 2008, $41 billion was paid by Medicaid and $50 billion was paid by private insurers [15]. The United States spent 17.6% of gross domestic product (GDP)

Table 1.1 U.S. maternity care data.

Measure U.S. International perspective Year

Cesarean section 32.8% 2011Preterm birth 11.72% 2011Maternal mortality 12.7/100,000 Higher than 49 developed countries 2007

African American women 26.5 2007White women 10.0 2007

Infant mortality 6.05/1,000 Higher than most OECD countries 2011African American infants 11.42 2011White infants 5.11 2011

Portion GDP to healthcare 17.6% Higher than all OECD countries 2010

The case for a physiologic approach to birth 5

on health care in 2010, more than any of the other OECD countries [6]. This phenomenon of doing more in perinatal care without a corresponding improvement in care outcomes was first referred to as the “perinatal paradox” more than 20 years ago [16]. Tremendous resources are allocated to maternal and infant care in the United States and yet our outcomes do not compare well with other developed countries. Although preterm birth has declined in recent years and the cesarean rate may have stabilized, there is much more work to be done.

The passage of the Affordable Care Act (ACA) in 2010 marked the first success in half a century of legislative attempts to change health care in the United States. When fully implemented, millions more Americans will have health care coverage. An important focus of the ACA is on improving health care and reducing costs by enhancing coordina-tion of care for individuals with chronic conditions, reducing medical errors, reducing hospital-acquired infections, and reducing waste in the system. Improving health care, improving care outcomes including client satisfaction, and providing care at lower cost, often referred to as the triple aim, are not only possible but necessary. In addition to improved access to health care, ACA improvements in care options for women include family planning and breast and cervical cancer screening without co-pays, coverage for maternity and newborn care, home-visiting services during pregnancy and early childhood, restricting insurance companies from charging women higher premiums than men, and enhanced support for breastfeeding mothers [17].

Concerns about the increased use of technology and medical intervention overuse in maternity care have been expressed by clinicians, scientists, educators, and others around the world. Multiple health professions and health-related organizations worldwide have issued statements calling for a more normal or physiologic approach to pregnancy and birth. Concerned with the rising rates of interventions in maternity care in the United Kingdom, the Maternity Care Working Party published a normal birth consensus statement in 2007, supported by the Royal College of Obstetricians and Gynecologists and the Royal College of Midwives, defining “normal delivery” as spontaneous labor, labor progression, and birth, without the use of interventions such as labor induction, epidural, cesarean section, and forceps. The statement proposes action steps to increase the proportion of normal births in the four UK countries [18]. Other statements, in some cases endorsed by multiple health professions organizations, have called for support of birth as a normal process, reduced intervention, use of best available evidence, and woman- centered care [19–22]. More recently, in the United States, the American Academy of  Family Physicians; American Academy of Pediatrics; American College of Nurse-Midwives; American College of Obstetricians and Gynecologists; American College of Osteopathic Obstetricians and Gynecologists; Association of Women’s Health, Obstetric and Neonatal Nurses; and Society for Maternal-Fetal Medicine endorsed a statement on quality patient care in labor and delivery identifying pregnancy and birth as normal processes requiring little if any intervention in most cases [23]. The authors called for effective communication, shared decision making, teamwork, and quality measurement in the provision of maternity care. Three U.S. midwifery organizations partnered in the development of a statement supporting physiologic birth—defining normal physiologic birth, identifying factors that disrupt and factors influencing normal birth, and proposing a set of actions to promote normal birth [24]. Reflecting the growing concern about

6 Supporting a Physiologic Approach to Pregnancy and Birth

the U.S. cesarean section rate, authors of a report summarizing a recent workshop held by the American Congress of Obstetricians and Gynecologists, the Society for Maternal-Fetal Medicine, and the Eunice Kennedy Shriver National Institute of Child Health and Human Development, plus a similar commentary, recommended specific practices and actions for clinicians and health systems to prevent the first cesarean section [25,26]. At least on paper, it seems as if we all agree.

Internationally, a series of normal labor and birth conferences have been held beginning in England in 2002 and most recently in China in 2012 [27]. The conferences highlight current research and best practices in promoting normal birth. In the United States, authors of a key report on evidence-based maternity care have identified induction of labor and cesarean section as overused procedures. Additionally, midwives, family physicians, and prenatal vitamins were described as underused interventions [28]. Following that report, Childbirth Connection, a nonprofit organization focused on improving maternity care, held a multistakeholder meeting focused on just how the quality and value of maternity care could be improved in the United States. The resulting “Blueprint for Action: Steps toward a High-Quality, High-Value Maternity Care System” provides clinicians, payers, educators, and care systems with excellent proposals to improve our care to women [29]. Strong Start for Mothers and Newborns, a federally funded program under the Centers for Medicare and Medicaid Services (CMS) Center for Medicare and Medicaid Innovation, has provided funding to reduce early elective births and to test new models of enhanced prenatal care to meet the triple aim. The models include enhanced prenatal care in group prenatal settings, in birth centers, and in maternity care homes [30].

In order to improve quality, health systems need to measure and report on the care provided [29,31,32]. Maternity care measures are available for use to improve quality such as the Joint Commission, the National Quality Forum, and the American Medical Association (AMA). The AMA Physician Consortium for Performance Improvement measure set was developed by an interprofessional work group and includes measures related to overuse of certain care practices as well as a measure for spontaneous labor and birth [33]. These quality measure sets are available to health systems, clinicians, and payers to improve care and achieve better care outcomes. In addition to the national measure sets, a tool to examine the optimal processes and outcomes of normal pregnancies among groups of women has been developed and tested. The Optimality Index-US measures what is “optimal” or best possible care processes and outcomes—within a  philosophy of aiming for the best outcome using the least number of interventions [34–36]. Higher Optimality scores in one setting over another may reflect an environment that supports a low intervention and physiologic approach to prenatal and labor care. Available as a research tool, clinicians can also use the index to examine institutional care processes and in peer review and other quality improvement processes [35].

Looking for something different

Women have signaled that they are beginning to look for something different, evidenced by the recent increase in out-of-hospital births [37]. After declining since 1990, home births increased by 29% from 2004 to 2009 [38]. In 2010, the increase in both home and

The case for a physiologic approach to birth 7

free-standing birth center births was large enough to cross the “99% mark,” documenting more than 1% of births occurring outside the hospital [2]. While the absolute number may not seem impressive (47,000 of nearly 4 million), the change is a message that a segment of the U.S. childbearing population is looking for something else. Birth is important to women, often a transformative event that they remember clearly throughout their lives. Many women believe labor and birth should not be interfered with and women understand their right to full information and to accept or refuse specific care processes [39]. Women are asking for specific services in hospitals such as water immersion, aromatherapy, and acupressure as part of the support tools available for labor and birth. Although epidurals remain popular, women are increasingly planning for an unmedicated birth and express a desire to be in control of their birth process [40]. The author of the 2011 consumer book Natural Birth in the Hospital: The Best of Both Worlds [41] reaches out to the nearly 99% of women giving birth in hospitals, letting them know that they, too, can have a more normal experience in a hospital and how to get what they want.

Women’s partnerships with their care providers are of utmost importance. Return for a moment to your clinic—sit down for a few more minutes with your client. What is it that she and her birth support persons really hope for during her labor and birth? What does the best evidence suggest are the preferred care measures resulting in the least harm? Take a little more time to engage in meaningful discussions with her so she puts aside her fears about labor, forgets the anxiety she’s seen in births depicted in the media, and partners with you in understanding options and planning for her labor and birth. When you welcome her to the hospital birthing room, tell her that your goal is to accommodate her and her partner’s preferences. Although it sounds easy, and most likely what we are trying to provide, current data support an alternate story.

This book can help you—the clinician “at the bedside”—take a look into the clinic exam rooms and hospital labor units to see what else is possible. The various chapter authors are clinicians and educators just like you. Together we have worked to summarize recent research and other published information and provide some ideas, tools, and solutions to put into the hands of maternity care clinicians including midwives, nurses, physicians, and others. The authors herein argue for supporting and enhancing women’s confidence in their ability to give birth. At the same time we aim to increase the confidence of care providers to trust in the normal process and support women expecting a healthy outcome rather than looking for reasons to disrupt the process. It goes without saying that specific conditions warrant medical intervention and higher levels of care such as pre-existing diabetes, hypertension, and multifetal gestation, and yet even women with those conditions can still be supported as mothers, enhancing normal or physiologic processes as much as possible.

A word about language. We have chosen to talk about an approach to physiologic pregnancy and birth with a profound respect for the intricate changes that occur during both pregnancy and labor that result in what is commonly referred to as “the miracle of birth.” We use the word “birth” in most cases, to honor the work that women do in giving birth. “Delivery” is retained in some circumstances, primarily to refer to women delivering their newborns. “Normal” is meant to signify the usual process of being pregnant and giving birth without being disturbed by technology or other interventions that are not necessary in supporting the usual processes [42], with no intent to judge any woman’s

8 Supporting a Physiologic Approach to Pregnancy and Birth

pregnancy or birth experience [43]. Every woman is unique; her process is also unique. Physiologic or normal is not just one variety or type, but each woman’s individual experience to be supported, “managing” only when the experience is truly outside the range of normal and thus requiring additional intervention. Even then, aspects of a normal or physiologic approach can be retained, always remembering the unique woman giving birth. Finally, this book is based on a belief that it takes all types of maternity care providers working in partnership to improve maternity care. Thus we refer to providers and clinicians, and the authors represent midwives, nurses, physicians, and others.

A look inside

Section 1 begins with a review of the normal physiologic changes of pregnancy as well as the physiologic uterine phases through pregnancy, labor initiation, continuation, and birth. Although the exact mechanism of the initiation of labor is not completely understood, the known components of pregnancy and labor physiology are fascinating, with increasing understanding through research on the intricacies of the labor process. With the goal of a physiologic approach as the norm, how do we adapt routine prenatal care to enhance women’s confidence and understanding of pregnancy as normal and not an illness to be treated? In a woman-centered approach, women are supported to understand the range of tools for comfort in early labor, how to recognize active labor and the best time to transition to the birthing unit (if not the home), and mechanisms to support the process. We work to bring women’s knowledge and understanding of the process as close to ours as possible and respect the knowledge and expertise each woman brings to her pregnancy. Originally proposed as a description of exemplary midwifery care, “the art of doing ’nothing’ well” [44] is recommended here as an approach for all clinicians providing maternity care unless there is a compelling reason to do something more.

Section 2 begins with a theoretical perspective on promoting comfort for women in labor followed by chapters describing integrative therapies for pregnancy, labor, and birth. Maternity care clinicians may not have sufficient knowledge and understanding about integrative or complementary and alternative medicine (CAM) practices [45]. Midwives appear to have a more positive view of the effectiveness of alternative therapies and are less likely to believe that results of CAM are due to placebo effect than obstetricians [46]. Researchers investigating nurse-midwives’ experiences with CAM therapies demonstrated that a majority of certified nurse-midwife respondents reported CAM use. Herbal preparations, pharmacologic/biologic, mind-body interventions, and manual healing/bioelectromagnetic therapies were used most often. Diet and lifestyle therapies were also common [47]. Women have increased their use of CAM therapies during preg-nancy, thus maternity care providers need to become knowledgeable about these practices and facilitate communication, cooperation, and respect among alternative and conven-tional providers [48].

Within the context of promoting comfort, chapters on relaxation, touch therapies, water immersion and water birth, acupuncture and acupressure, and aromatherapy are offered as adjuncts to “doing nothing” in support of women during pregnancy, labor, and birth.

The case for a physiologic approach to birth 9

While not an exhaustive representation of possible integrative therapies, reviews of evidence and practical suggestions are offered as tools for maternity care clinicians to assist women in achieving their preferred birth experience. Authors aim to help clinicians understand these therapies better, including specific instructions on how to use certain techniques, as well as information on referring to providers of the therapy and how specific practices, such as acupuncture, are regulated.

Finally, section 3 focuses on the broader care and education systems. Individual clini-cians can provide excellent one-on-one care and effect local change. In order to change maternity care in the United States, we must also work within our broader systems to shift to a more physiologic approach. Because nearly 99% of births occur in hospitals, the best opportunity to effect meaningful system change is to adjust the approach to care on labor units. Nurses are key in making that happen, and a group of labor nurses have proposed a possible solution after examining available evidence and related information. The other 1% of births occur outside the hospital; evidence supports the safety of this approach for carefully selected women when out-of-hospital practice is imbedded in a broader system of consultation and referral to more intensive care when needed. Respecting out-of- hospital birth as a safe environment for low-risk women who desire that care is critical. When transfer to the hospital setting is required, the process of transfer and receiving the woman and her family can be more seamless and positive with enhanced understanding and respect among clinicians from both settings.

For the change we desire to be permanent and system-wide, we must promote interprofessional collaborative practices that are built on a foundation of mutual trust and respect, with care decisions made by informed women and their families [23,24,49,50]. Maternity care providers must be educated together so that they will provide the seamless quality care women deserve, with clinical education occurring in environments where students learn with interprofessional care teams. Policy changes to support clinicians practicing together to the full extent of their education and training, in an environment where all women have access to quality health care, is the final critical component to improving maternity care. Legislators and policy-makers need to hear from their constituent clinicians in making those necessary changes.

National attention is focused on maternity care in a way that has not been seen in recent history, providing an opportunity to be transformative [29]. This group of authors, representing committed clinicians, educators, and researchers from multiple professions, invites you to come along on a journey to serve women today to build tomorrow’s healthier families. Women and their families deserve the very best that we can collec-tively provide in an environment that respects pregnancy and birth as normal processes, that respects the women and their families/support networks to lead their care, and where we respect and trust each other as partners in providing excellent care. The change required is larger than any one clinician or profession can accomplish. Indeed, we are encouraged that health professionals are responding to calls for interprofessional practice and education. While we add our voices to the larger discussions in Congress, federal health-related agencies, educational settings, and corporate boardrooms, a more quiet yet powerful change can occur in our care settings through the conversations and plans we make with each other and with our clients every day—clinic by clinic, woman by woman, birth by birth.

10 Supporting a Physiologic Approach to Pregnancy and Birth

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The case for a physiologic approach to birth 11

18. Maternity Care Working Party. (2007). Making normal birth a reality. Consensus statement from the Maternity Care Working Party. Available from: http://www.nct.org.uk/professional/research/pregnancy-birth-and-postnatal-care/birth/normal-birth. Accessed November 24, 2012.

19. Canadian Association of Midwives. (2010). Midwifery care and normal birth. http://www. aom.on.ca/files/Communications/Position_Statements/CAMNoramalBirth_ENG201001.pdf. Accessed November 24, 2012.

20. International Confederation of Midwives. (2008). Keeping birth normal. http://international midwives.org/assets/uploads/documents/Position%20statements%20-%20English/PS2008_007%20ENG%20Keeping%20Birth%20Normal.pdf. Accessed November 24, 2012.

21. New Zealand College of Midwives. (2006). NZCOM consensus statement normal birth. http://www.midwife.org.nz/index.cfm/3,108,559/normal-birth-ratified-agm-2006-refs-2009.pdf. Accessed November 24, 2012.

22. Society of Obstetricians and Gynaecologists of Canada. (2008). Joint policy statement on normal childbirth. Journal of Obstetrics and Gynaecology Canada, 30(12), 1163–1165. http://www.sogc.org/guidelines/documents/gui221PS0812.pdf. Accessed November 24, 2012.

23. American Academy of Family Physicians; American Academy of Pediatrics; American College of Nurse-Midwives; American College of Obstetricians and Gynecologists; American College of Osteopathic Obstetricians & Gynecologists; Association of Women’s Health, Obstetric and Neonatal Nurses; & the Society for Maternal-Fetal Medicine. (2012). Quality patient care in labor and delivery: A call to action. Journal of Midwifery & Women’s Health, 57, 112–113.

24. American College of Nurse-Midwives, Midwives Alliance of North America, & National Association of Certified Professional Midwives. (2012). Supporting healthy and normal physi-ologic childbirth: A consensus statement by ACNM, MANA, and NACPM. http://www. midwife.org/ACNM/files/ACNMLibraryData/UPLOADFILENAME/000000000272/Physiological%20Birth%20Consensus%20Statement-%20FINAL%20May%2018%202012%20FINAL.pdf. Accessed November 15, 2012.

25. Spong CY, Berghella V, Wenstrom KD, Mercer BM, & Saade GR. (2012). Preventing the first cesarean delivery. Summary of a Joint Eunice Kennedy Shriver National Institute of Child Health and Human Development, Society for Maternal-Fetal Medicine, and American College of Obstetricians and Gynecologists Workshop. Obstetrics & Gynecology, 120(5), 1181–1193. DOI: http://10.1097/AOG.0b013e3182704880.

26. Main EK, Morton CH, Melsop K, Hopkins D, Giuliani G, & Gould J. (2012). Creating a public agenda for maternity safety and quality in cesarean delivery. Obstetrics & Gynecology, 120, 1194–1198. DOI: http://10.1097/AOG.0b013e31826fc13d.

27. Hanzhou Normal University. (2012). http://www.iresearch4birth.eu/iResearch4Birth/resources/cms/documents/China_English_flyer.pdf. Accessed November 23, 2012.

28. Sakala C & Corry M. (2008). Evidence-based maternity care: What it is and what it can achieve. Co-published by Childbirth Connection, the Reforming States Group, and the Milbank Memorial Fund. Available at: http://www.childbirthconnection.org/pdfs/evidence-based- maternity-care.pdf.

29. Transforming Maternity Care Symposium Steering Committee. (2010). Blueprint for action: Steps toward a high-quality, high-value maternity care system. Women’s Health Issues, 20, S18–49.

30. Centers for Medicare and Medicaid. (2012). http://www.innovations.cms.gov/initiatives/strong-start/index.html. Accessed November 28, 2012.

31. Joint Commission. (2010). Perinatal care measures. http://manual.jointcommission.org/releases/TJC2011A/PerinatalCare.html. Accessed November 6, 2012.

32. National Quality Forum. (2012). Endorsement summary: Perinatal and reproductive health measures. http://www.qualityforum.org/News_And_Resources/Endorsement_Summaries/Endorsement_Summaries.aspx. Accessed November 6, 2012.

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12 Supporting a Physiologic Approach to Pregnancy and Birth

33. American Medical Association and the National Committee for Quality Assurance. (2012). Maternity care performance measurement set. http://www.ama-assn.org/resources/doc/cqi/ no-index/maternity-care-measures.pdf. Accessed November 24, 2012.

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50. Avery MD, Montgomery O, & Brandl-Salutz E. (2012). Essential components of successful collaborative maternity care models: The ACOG-ACNM Project. Obstetrics and Gynecology Clinics of North America, 39, 423–434. DOI: 10.1016/j.ogc.2012.05.010.

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Supporting a Physiologic Approach to Pregnancy and Birth: A Practical Guide, First Edition. Edited by Melissa D. Avery. © 2013 John Wiley & Sons, Inc. Published 2013 by John Wiley & Sons, Inc.

The physiology of pregnancy, labor, and birthCindy M. Anderson

[I]t is time that professionals regain their trust in the physiology which enables healthy women to labour and deliver, mostly without interference.

Marianne Mead

Chapter 2

Key points

• The placenta is the interface between the mother and fetus supporting perfusion to meet fetal growth and development needs; transport is influenced by placental area, diffusing distance, permeability of placental barrier, and maternal-fetal blood flow in the intervillous spaces.

• The placenta assumes the neuroendocrine functions that are regulated in the nonpregnant state by the typical hypothalamus-pituitary-end organ feedback mechanisms.

• Progesterone is the dominant hormone during pregnancy, its inhibitory effects largely responsible for the uterine quiescent phase during pregnancy.

• To meet the increased demand for maternal and fetal oxygen and oxygen transport during pregnancy, cardiac output, oxygen consumption, and left ventricular stroke volume increase, along with a 40% increase in blood volume primarily comprised of the plasma component. Maternal pulmonary tidal volume and inspiratory capacity increase while residual volume, expiratory reserve volume and functional residual capacity decline.

• Changes in the firm cervical structure to more pliable and distensible occur in later preg-nancy as water concentration increases relative to collagen, resulting from an increase in highly hydrophilic glycoaminoglycans such as chondroitin sulfate and hyaluronan.

• The complex signaling between mother, placenta, and fetus that triggers labor initiation and progression are not completely understood, however likely involve the interplay among hormonal, mechanical, and immune factors.

• The transition from progesterone dominance in the uterine quiescent phase to the estrogen dominance in the activation phase stimulates coordinated, synchronous con-tractions in myometrial cells in the contractile fundus. Uterine contractions are promoted by increased myometrial oxytocin receptors and increased prostaglandin production in the fetal membranes.

• Stress and anxiety during labor can be exacerbated by fear, thus triggering cognitive pain perception and increasing sensitivity to pain.

14 Supporting a Physiologic Approach to Pregnancy and Birth

Introduction

The processes of the initiation and progression events characteristic of the intrapartum period are critically important for optimal care of pregnant women, yet the underlying mechanisms of labor physiology are poorly understood. The physiologic changes of pregnancy are necessary to prepare women for the unique challenges brought on by the significant demands placed on multiple maternal body systems, required to support ideal function of the maternal-placental-fetal unit. The intrapartum period presents new chal-lenges associated with unique adaptations associated with initiation and progression of labor, culminating in birth of a newborn and the return to maternal prepregnant physio-logic function. Theories surrounding the relatively mysterious biochemical events that prompt intrapartum events abound, though a single explanation for the processes of labor and birth is elusive. The complex signaling between mother, placenta, and fetus that triggers labor initiation and progression is unclear but likely involves interplay between hormonal, mechanical, and immune factors. This chapter presents a detailed discussion of maternal physiologic adaptations in pregnancy as well as labor and birth and the known and postulated mechanisms surrounding the intrapartum events of labor and delivery.

Physiologic adaptive changes in pregnancy

Adaptations of maternal physiology during pregnancy involve the accommodations in multiple systems to support the increasing demands with progressive gestation. Pregnancy adaptations are essential foundations for the unique adjustments required to support the processes of labor and to support the increased demands placed on the maternal-placental-fetal unit during the intrapartum period. Pregnancy can be considered in four separate phases: quiescence, activation, stimulation, and involution [1]. The antepartum period prior to the onset of labor is characterized by quiescence, suppression of uterine activity, reflecting the exquisite balance between the hormonal mileu and responsiveness of the uterus and cervix. Quiescence is mediated by inhibitor hormones, including progesterone, prostacyclin, relaxin, nitric oxide (NO), corticotropin-releasing hormone (CRH), and human placental lactogen (hPL).

Placenta

The placenta, formed by the union of the maternal decidua basalis and the fetal trophoblast, develops in the early days of pregnancy with implantation of the blastocyst. Placental growth continues throughout gestation until term, when the average surface area reaches 12.6 m2, increasing to a functional surface area of 90 m2 when microvilli surface is considered. Placental weight at term equals approximately 500 g, with dimensions of a diameter of 15–20 cm and thickness of 3 cm [2, p. 3].

The placenta serves as the interface between mother and fetus, supporting perfusion to meet fetal needs in the intrauterine environment. Progressive placental vascular development is stimulated by the hypoxic intrauterine environment characteristic of early pregnancy. Fetal deoxygenated blood passes from the dual umbilical arteries to the placenta.