Relaxation During Pregnancy to Reduce Stressand Anxiety and Their Associated Complications

Item Type text; Electronic Dissertation

Authors Chambers, Andrea Suzanne

Publisher The University of Arizona.

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RELAXATION DURING PREGNANCY TO REDUCE STRESS AND ANXIETY AND THEIR ASSOCIATED COMPLICATIONS

by

Andrea S. Chambers

_____________________ Copyright © Andrea S. Chambers 2007

A Dissertation Submitted to the Faculty of the

DEPARTMENT OF PSYCHOLOGY

In Partial Fulfillment of the Requirements For the Degree of

DOCTOR OF PHILOSOPHY

In the Graduate College

THE UNIVERSITY OF ARIZONA

2007

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THE UNIVERSITY OF ARIZONA GRADUATE COLLEGE

As members of the Dissertation Committee, we certify that we have read the dissertation prepared by Andrea Suzanne Chambers entitled Relaxation During Pregnancy to Reduce Stress and Anxiety and Their Associated

Complications

and recommend that it be accepted as fulfilling the dissertation requirement for the

Degree of Doctor of Philosophy. Date: November 2, 2007 John J. B. Allen Date: November 2, 2007 Varda Shoham Date: November 2, 2007 Richard Bootzin _ Date: November 2, 2007

Jean Williams Final approval and acceptance of this dissertation is contingent upon the candidate’s submission of the final copies of the dissertation to the Graduate College. I hereby certify that I have read this dissertation prepared under my direction and recommend that it be accepted as fulfilling the dissertation requirement. ________________________________________________ Date: November 2, 2007 Dissertation Director: John J. B. Allen

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STATEMENT BY AUTHOR This dissertation has been submitted in partial fulfillment of requirements for an advanced degree at the University of Arizona and is deposited in the University Library to be made available to borrowers under rules of the Library. Brief quotations from this dissertation are allowable without special permission, provided that accurate acknowledgment of source is made. Requests for permission for extended quotation from or reproduction of this manuscript in whole or in part may be granted by the copyright holder. SIGNED: Andrea Suzanne Chambers

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ACKNOWLEDGEMENTS I’d like to thank the Philanthropic Educational Organization awarding me the 2005 Scholar Award that funded this research and the General Clinical Research Center at the University of Virginia for their services. This study would not have been possible without the research assistants, obstetric clinics, midwives, Charlottesville Birth Circle, prenatal yoga instructors, prenatal massage therapists, research consultants, and mentors. In particular I’d like to thank Patricia Lee Lewellyn, Annalisa Smith, Myo Sabai Aye, Catherine Thrasher, Emily Marston, Erin Miga, Mandy Steiner, Aidalida Altamirano, Elizabeth Gramlich, Heather Abercrombie, Susan Kirk, Susan Lashley, Hugh Miller, Jonathan C. Forster, David Towers, Lisa Goehler, Lynne Simpson, and Helena Estes-Johnson. Thank you to the women who participated in this study and tirelessly answered numerous questionnaires, performed mental arithmetic while being told somewhat obnoxiously to work faster, and in countless ways shared this very important time of life with this project. Thank you to the Department of Psychology at the University of Virginia for providing office space and administrative support; in particular I’d like to thank David Hill, Donna Hearn, Eric Turkheimer, Morgan Davis, and Debbie Snow. Thank you to my committee—John Allen, Varda Shoham, Dick Bootzin, and Jean Williams for sharing their research ideas and wise words. Thank you for agreeing to be members on both my comprehensive exams and dissertation committees. You’ve truly been the dream team! Thank you to my mentor, John Allen, for encouraging me to take on this project for my dissertation despite its subject area being tangential to your own and thank you for your limitless mentorship and giving me my start with research in your lab over ten years ago! Thank you to mom and dad who gave me my very first grant for this study and your unwavering support. Thank you, Jim, for being my biggest supporter and believing in and reassuring me when I didn’t think I could complete this project!

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DEDICATION I dedicate this dissertation to myself. I have finally discovered that the sunshine I had always sought was embodied in me all along.

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TABLE OF CONTENTS LIST OF TABLES ....................................................................................................... 9

LIST OF FIGURES.................................................................................................... 10

ABSTRACT .............................................................................................................. 11

INTRODUCTION..................................................................................................... 12

Background............................................................................................................. 12

Consequences During Pregnancy........................................................................ 12

Potential Mechanisms ......................................................................................... 15

Reducing Stress During Pregnancy ..................................................................... 16

Progressive Muscle Relaxation............................................................................ 17

Objectives ........................................................................................................... 18

METHODS................................................................................................................ 20

Participants ............................................................................................................ 20

Procedure................................................................................................................ 21

Laboratory Based Assessments ........................................................................... 21

Intervention Procedures ...................................................................................... 23

Measures................................................................................................................ 25

Measures of Mood .............................................................................................. 26

Moderators of Stress........................................................................................... 27

Health Behaviors ................................................................................................ 28

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TABLE OF CONTENTS - Continued

Practice of Relaxation Methods............................................................................ 28

Working Alliance Inventory................................................................................. 29

Gestational and Obstetric Complications............................................................. 29

Infant Measures .................................................................................................. 30

Physiological Measures....................................................................................... 30

Physiological Data Reduction.............................................................................. 31

Statistical Analyses ................................................................................................ 32

RESULTS .................................................................................................................. 33

Demographics ........................................................................................................ 33

Specific Aim One ................................................................................................... 33

Feasibility of providing Relaxation Training to Highly Stressed

Pregnant Women ................................................................................................ 33

Reduce Negative Mood in Stressed Pregnant Women........................................... 34

Specific Aim Two................................................................................................... 40

Birth Outcomes ................................................................................................... 40

Exploratory Aim..................................................................................................... 42

Physiological Changes ........................................................................................ 42

Psychological Predictors of Birth Outcomes and Infant Variables........................ 44

Physiological Moderators and Predictors of Outcome ......................................... 46

DISCUSSION ............................................................................................................ 51

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TABLE OF CONTENTS - Continued

Feasibility............................................................................................................... 51

Relaxation as an Intervention for Reducing Negative Mood.................................... 52

Relaxation as an Intervention for Reducing Complications During Pregnancy ........ 52

Physiological changes over pregnancy.................................................................... 54

Independent Predictors of Outcome ........................................................................ 55

Future Directions.................................................................................................... 56

REFERENCES........................................................................................................... 58

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LIST OF TABLES Table 1. Summary of measures and timing of completion............................................ 25

Table 2: Means and standard deviations for the main outcome measures of stress,

depression, and anxiety............................................................................................... 34

Table 3. Ranges, semi-partial r’s, and significant F-change from regression that predicted

post-treatment symptoms from the frequency of relaxation practice after accounting for

the baseline symptom................................................................................................. 36

Table 4 Ranges, semi-partial r’s, and significant F-change from regression that predicted

post-treatment symptoms from the subscales of the Working Alliance Inventory after

accounting for the baseline symptom .......................................................................... 38

Table 5. Frequency of complications per treatment group and infant measures ........... 40

Table 6: Means and standard deviations of the physiological signals during tasks across

time. ........................................................................................................................... 43

Table 7. Ranges, semi-partial r’s, and significant F-change from regression that predicted

post-treatment symptoms from baseline RSA after accounting for the baseline

symptom.................................................................................................................... 48

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LIST OF FIGURES Figure 1. Average frequency of relaxation practice per week and unstandardized residuals

of A) Perceived Stress Scale at Time 2, B) Perceived Stress Scale at Time 3, C) Edinburgh

Depression Scale (EDS) at Time 3 and D) State Anxiety Inventory at Time 3............. 37

Figure 2. Working Alliance Inventory Subscale and unstandardized residuals: A) DASS

Depression Scale at Time 2, and Client-Rated Goal B) DASS Depression Scale at Time 2

and Therapist-Rated Bond, C) Edinburgh Depression Scale (EDS) at Time 3 and

Therapist-Rated Task, and D) Perceived Stress Scale at Time 3 and Therapist-Rated

Task. .......................................................................................................................... 39

Figure 3. The average frequency of practicing relaxation methods in the relaxation treatment

group for those who did and did not experience a gestational complication................................41

Figure 4. The difference in the level of negative mood between those women who experienced a

gestational complication versus those who did not........................................................................45

Figure 5. Resting RSA at Time 1 predicted trait anxiety at Time 2 for those in the relaxation

treatment group (semi-partial r = .57) but not for those in the self-care group. ...........................46

Figure 6. Resting baseline respiratory sinus arrhythmia (RSA) and unstandardized residuals of

Time 3: A) DAS Depression Scale, B) Edinburgh Depression scale (EDS), C) State Anxiety

Inventory (SAI), D) Trait Anxiety Inventory (TAI), and E)Perceived Stress Scale....................49

Figure 7. Group differences in resting RSA at Time 1 in women who did and did not experience

gestational complications.................................................................................................................50

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ABSTRACT

Stress and anxiety during pregnancy predict perinatal complications over the course of

pregnancy and labor as well as premature birth and low infant birth weight. The current

study examined whether relaxation training provided to women at the beginning of the

2nd trimester could reduce stress and anxiety and assessed the impact of the intervention

on perinatal complications, premature delivery, and infant outcomes at birth. Twenty-six

moderately anxious pregnant women between 14 and 20 weeks gestation participated in

the treatment study. Women completed a baseline laboratory assessment that involved

questionnaires and a psychophysiological assessment. They were randomized to receive

either six weeks of relaxation training or a list of tips for reducing stress (control).

Women repeated the laboratory tasks post-treatment (Time 2) and again between 34 and

36 weeks gestation (Time 3). The treatment condition did not lead to greater mood

change than the control condition at either Time 2 or 3. Several analyses, however,

suggest relaxation training has the potential for reducing negative mood and

complications over the course of pregnancy. Moderator analyses also revealed the

treatment more efficacious for those with greater physiological flexibility.

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INTRODUCTION

Stress and anxiety during pregnancy predict complications over the course of

pregnancy, as well as prematurity and low infant birthweight, even after controlling for

sociodemographic and behavioral risk factors. Prenatal stress and anxiety levels also

have implications for the developing child, even through adolescence. Given these links

between prenatal maternal stress and infant development, it is noteworthy that few

studies have attempted to reduce stress and anxiety during pregnancy. The current study

sought to test whether relaxation training provided to women at the beginning of the 2nd

trimester could reduce pregnancy complications and negative infant outcomes.

Background

Consequences During Pregnancy. Stress has deleterious health effects, which are of

increased concern during pregnancy. Stressors come in many forms, including

significant life events (e.g. death of a loved one), chronic stress (e.g., a demanding job),

or a series of daily hassles that prevent the body from returning to homeostasis. The

perception of such stress results in sympathetic nervous system activation, resulting in the

release of norepinephrine and epinephrine, which produce a cascade of physiological

responses (e.g. increased heart rate, blood pressure, oxygen consumption) to promote

“fight or flight” as well as deactivation of some homeostatic processes (e.g.

vasoconstriction of the arteries to the skin and stomach). The Hypothalamic-Pituitary-

Adrenal (HPA) cascade involves the release of corticotrophin releasing hormone (CRH)

from the hypothalamus to the pituitary gland, leading to a release of adreno-

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corticotrophin hormone (ACTH) that stimulates the adrenal gland to release cortisol.

Cortisol assists in the process of metabolizing glucose for energy from sources of protein.

If the HPA axis is not deactivated, however, high levels of cortisol can impact the health

of the organism, as the immune system provides a plentiful source of protein.

Stress, in relation to pregnancy, has been measured in a number of ways: by counting

the frequency and rating the severity of daily hassles or significant life events during the

course of pregnancy, as a personality construct of trait anxiety, in terms of state anxiety,

and as the extent of fear associated with different aspects of the pregnancy (e.g. fear of

giving birth). All of these dimensions of stress place a woman at risk to more

complications during pregnancy (Beck et al., 1980; Clifford, Weaver, & Hay, 1989;

Copper et al., 1996; Da Costa, Brender, & Larouche, 1998; Da Costa, Larouche, Drista,

& Brender, 1999; Field et al., 2001; Norbeck & Tilden, 1983). For example, two

independent studies (Clifford et al., 1989; Da Costa et al., 1998) have found that greater

prenatal stress in the first trimester was related to more complications during pregnancy

(e.g. eclampsia), more labor difficulties (e.g. emergency Caesarean section), and more

negative infant outcomes (e.g. prematurity). Another study (Norbeck & Tilden, 1983)

found that stress interacted with social support such that women who experienced more

life stressors and were provided with less financial and informational support had the

highest rate of pregnancy and infant condition complications.

The multiple dimensions of stress have also predicted preterm birth (less than 37

weeks gestation) after accounting for obstetric complications, the number of previous

pregnancies, and health behaviors (e.g. smoking during pregnancy). Several studies

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suggest that a greater number of life events occurring within the last twelve months and

during pregnancy increases the risk for preterm delivery (Berkowitz & Kasl 1983;

Whitehead, A, Brogan, & Blackmore-Prince, 2002) and that the risk is greater for those

events occurring earlier in the pregnancy (Berkowitz & Kasl 1983; Glynn, Wadhwa,

Dunkel-Schetter, Checz-DeMet, & Sandman, 2001). Four studies suggest that prenatal

pregnancy-specific anxiety (Orr, Reiter, Blazer, & James, 2007; Rini, Dunkel-Schetter,

Wadhwa, & Sandman, 1999; Wadhwa, Sandman, Porto, Dunkel-Schetter, & Garite,

1993) and general state or trait anxiety (Rondó, Ferreira, Nogueira, Ribeiro, Lobert et al,

2003) were related to premature delivery. For example, Wadhwa et al. (1993) found that

each incremental unit increase of prenatal pregnancy-specific anxiety (a total of 5 units

on the scale) was associated with a 3-day decrease in gestational age at birth. This study

was later replicated by Rini and colleagues (1999).

Stress as measured by state and trait levels of general anxiety or pregnancy-

specific anxiety, or as measured by life events, has also predicted birth length (Casko,

2003) and weight (Collins, Dunkel-Schetter, Lobel, & Scrimshaw, 1993; Feldman,

Dunkel-Schetter, Sandman, & Wadhwa, 2000; Field, Diego, Hernandez-Reif, Schanberg,

Kuhn et al, 2003; Rondó et al., 2003; Suzuki, Minai, Yamagata, 2007), with more stress

associated with decreased birthweight, including an increased likelihood of giving birth

to infants who weigh less than 2500 grams (Field et al., 2003). This latter finding is

especially noteworthy in that infants between 1500-2500 grams are five times more likely

to die in first year of life than normal-weight infants (McCormick, 1985). Social support

(Collins et al, 1993; Feldman et al, 2000) and optimism (Lobel, DeVincent, Kaminer, &

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Meyer, 2000; Rini et al, 1999) have been found to moderate the relationship between

stress and infant birth weight. For example, Collins et al (1993) interviewed 129 women

in the beginning of the 2nd trimester about social support, stress, and depression

throughout their pregnancy. When life events were low, social support was unrelated to

infant birth weight but when life events were high, more social support quality predicted

higher birth weight and, in a separate set of analyses, fewer maternal depressive

symptoms in the postpartum period.

Potential Mechanisms. Three pathways have been posited to explain the effects of

stress on pregnancy, particularly on premature delivery and pregnancy complications:

cardiovascular vasoconstriction, neuroendocrine effects, and immune inflammatory

responses. Changes in maternal cardiovascular function have been posited to restrict

uterine blood flow that interferes with vital supplies to the fetus which in turn leads to a

fetal stress response and a release of cortisol (Ascher, 1978; Sjostrom, Valentin, Thelin,

& Marsal, 1997). In the only study to investigate stress reactivity in relation to infant

birth and prematurity (McCubbin, Lawson, Cox, Sherman, Norton et al, 1996) women

with larger diastolic blood pressure responses during a cognitive stressor had infants with

lower birth weight and decreased gestational age. It has been posited that more muscle

tension during stressful situations in later phases of the pregnancy potentiates early

contractions, triggering preterm labor (Paarlberg, Vingerhoets, Passchier, Dekker, & Van

Geijn, 1995).

Neuroendocrine effects may result from maternal stress activating the HPA axis which

results in a release of both ACTH and cortisol (Wadhwa Culhane, Rauh, Barve, Hogan et

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al, 2001). These hormones increase levels of CRH in the placenta, facilitating the shift in

balance between progesterone and estrogen, and resulting in premature parturition.

Indeed, placental CRH concentrations in the third trimester of gestation negatively

predicted gestational length, earlier onset of labor, and preterm labor (Wadhwa, Porto,

Garite, Chicz-DeMet, & Sandman, 1998).

The third pathway involves the immune system but is not well understood (Wadhwa et

al., 2001). Preterm birth is associated with increased levels of pro-inflammatory

cytokines, which are purported to fight genital tract infections and/or by an irregular

dominance of the cellular immune system over the humoural immune system. Increased

levels of proinflammatory cytokines cause an increase in fetal cortisol and placental CRH

release, promoting premature parturition. Over the course of a typical pregnancy,

lymphocytes released by the humoural immune system progressively decrease their

responsiveness to proinflammatory cytokines. Stress interacts with this process such that

cortisol further decreases the levels of lymphocytes as sources of protein, maintaining,

high levels of proinflammatory cytokines. Moreover, high levels of maternal

psychological stress and low levels of social support in pregnant women were associated

with even lower levels of lymphocytes (Herrera, Alvarado, & Matrinez, 1998).

Reducing Stress During Pregnancy. Few studies have targeted pregnant women for

relaxation training during pregnancy, but the results are promising. Weekly training

sessions in deep muscle relaxation and cognitive control techniques for five weeks have

been found to reduce cognitive and emotional manifestations of stress (de Anda, Darroch,

Davidson, Gilly, & Morejon, 1990) and state and trait levels of anxiety (Liebman &

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MacLaren, 1991) in pregnant adolescents and adolescent mothers. Similarly, hypnotic

relaxation in addition to medication prolonged pregnancy in women who were

hospitalized for premature contractions and resulted in greater infant weight than in

women who only received medications (Omer, Friedlander, & Palti, 1986). No study to

date has examined whether reducing anxiety and stress during pregnancy can reduce the

incidence of pregnancy complications, including premature delivery, and low birth

weight. The proposed study thus sought to provide a low cost and time efficient method

for treating anxiety and stress—progressive muscle relaxation—in pregnant women

during the beginning of their 2nd trimester.

Progressive Muscle Relaxation. Progressive muscle relaxation (PMR) was originally

developed by Jacobson (1938) and later manualized in an abbreviated format by

Bernstein and Borkovec (1973). PMR involves tensing and relaxing a series of 16

muscle-groups to achieve deep relaxation and has been used to treat both physical

ailments (e.g. migraine and tension headaches, cancer chemotherapy side effects,

hypertension) and psychological problems (e.g. adolescent depression, Generalized

Anxiety Disorder, and recovery from stress). Carlson and Hoyle (1993) conducted a meta

analysis of the effects of PMR and found moderate effects sized at .4 when comparing

pre- to post-relaxation changes. PMR was more effective when taught individually than

in groups, when the participants were provided training tapes, and when there are

multiple training sessions (Carlson & Hoyle, 1993). The effects of PMR increased in

effectiveness over time and equally impacted psychological (e.g. 25% reduction in

anxiety) and physiological measures (e.g. decreases in heart rate and blood pressure

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(Carlson & Hoyle, 1993). Progressive muscle relaxation has also been shown to result in

vasodilation (Pawlow & Jones, 2002), in the reduction of cortisol (Pawlow & Jones,

2002; Smyth, Litcher, & Hurewitz, 2001), and an increase in cytokines (Pawlow,

2003)—the same pathways implicated in mediating the effects of stress on pregnancy and

on the fetus.

Objectives. The primary objectives of the proposed study were to examine whether six

weeks of training in a variety of relaxation methods could reduce stress and anxiety

during pregnancy and whether this intervention could reduce perinatal complications,

including preterm birth and low birth weight. The present study had two primary specific

aims:

1. To determine the feasibility of providing relaxation training to a group of

highly stressed women for reducing levels of stress and anxiety.

Goal 1: To determine the feasibility via rates of recruiting eligible women,

rates of compliance to protocol, and drop out rates.

Goal 2: To reduce negative mood in women randomly assigned to

relaxation training in comparison to a group of women who received

general advice for reducing stress.

2. To determine whether the intervention could reduce rates of complications during

pregnancy, labor, and delivery as well as negative infant outcome.

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3. Exploratory Aims

Goal 1: To examine whether various physiological systems were affected by the

intervention and whether such changes mediated the impact of stress reduction

on the pregnancy and infant outcomes.

Goal 2: To examine whether baseline psychological and physiological variables

could moderate treatment outcome or be an independent predictor of outcomes.

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METHODS Participants.

From among 64 women who responded to advertisements about the study, 26 women

were eligible to participate. Recruitment efforts involved distributing flyers at obstetric

and mid-wife offices, prenatal yoga studios, prenatal massage studios, religious

institutions (e.g. churches), and public events (e.g. Farmer’s Market); paid advertising

included newspapers, newsletters, public television, and internet sites. Eligible women

were between 18 to 40 years old, were within the range of 14 to 20 weeks gestation of

pregnancy, had no more than 1 miscarriage, and scored 40 or more points on either the

state or trait scales of the State Trait Anxiety Inventory (STAI). Several studies have used

a cutoff of 40 or more on the STAI for study eligibility (Rondó et al., 2003), to indicate

the minimal level of anxiety for a “high anxiety group” (Field et al., 2003) and this score

was found to be 1 standard deviation above the mean (Brouwers, van Baar, & Pop, 2001).

Women were excluded if they met criteria for an Axis I Disorder, were currently

using street drugs, were receiving psychological services for coping with mood or stress

and were unwilling to discontinue, and if they were currently taking anti-depressant or

anti-anxiety medications. Additionally, women were excluded if they currently had

biological children or if they had more than one previous miscarriage. Research suggests

women with multiple pregnancies experience less stress than women who are pregnant

for the first time; (Da Costa, et al., 1998; Rondó et al, 2003) and women with multiple

pregnancy tend to have fewer complications (Da Costa et al, 1998) than women who

were pregnant for the first time.

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Procedure.

Laboratory Based Assessments. Upon determining eligibility, women were invited to the

research laboratory for two separate visits. The first visit involved obtaining informed

consent followed by the administration of the Structured Clinical Interview Based on the

Diagnostic Statistical Manual IV (First, Spitzer, Gibbon, & Williams, 1994) by a

Masters-level graduate student. At the second visit participants completed a series of

questionnaires and signed a release for medical information for their obstetrician to allow

study personnel to obtain a copy of their medical charts. Women had the following

physiological signals recorded for five minutes while the participants sat with their eyes

closed: heart rate, respiration, skin conductance, and electromyography (EMG) from the

lateral frontalis muscle from the non-dominant side of the body and from the

gastrocnemius muscle of both legs. As described previously these physiological signals

index several of those mechanisms that are purported to be responsible for the impact of

mood on pregnancy complications and birth outcomes. Greater cardiac vagal control,

derived from heart rate and respiration, is generally related to better health outcomes and

more immune system activity and might confer protective health benefits (Masi,

Hawkley, Rickett, & Cacioppo, 2007; Thayer & Lane, 2007).

Participants then engaged in two mildly stressful and commonly employed

experimental tasks, in counterbalanced order according to whether the participant’s id

number was even or odd, for five minutes followed by a five-minute recovery period

after each stressor. The two stressors were mental arithmetic (where participants must

count backwards by 7’s) and the Stroop Color Word Task (the names of colors are

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displayed and the printed text is in either matching or mismatching color). The Stroop

task required the participants to name the color of the printed word. At one-minute

intervals during both tasks the experimenter provided prompts (i.e. “Please work faster.”;

“Please try not to make as many mistakes”; “Don’t hesitate before you respond, just go

with your gut”) to increase the stressfulness of the tasks. Both of these tasks have elicited

increases in heart rate, respiration, and skin conductance in anxious and non-anxious

pregnant populations and participants have described these tasks as stressful in previous

studies (DiPietro, Costigan, & Gurewitsch, 2003; DiPietro, Costigan, Gurewitsch, 2005;

Monk et al, 2003; Monk et al, 2001).

While the aforementioned tasks are reliable methods for eliciting physiological arousal,

the extent to which they reflect “real world” stressors is dubious. Upon completion of the

mental arithmetic and the Stroop Color Word tasks, participants were asked to describe a

recent situation in which they last felt stressed or anxious. The experimenter then asked

participants to imagine the situation as vividly as possible for two minutes as the

participant’s physiology was recorded.

The participants were then asked to try to relax for the next two minutes. This

relaxation task allowed for an examination of baseline relaxation skills at intake and

during the post-treatment assessments the task served as an objective outcome measure

for how well the relaxation participants learned the relaxation methods. The relaxation

phase was followed by five more minutes of recovery. Before and after each stressor,

participants were asked to rate their current level of stress on a range from one to ten,

where ten was “extremely stressed” and 1 was “not stressed at all”. After the

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visualization tasks participants were asked to indicate the amount of time they were

engaged in the task and how vivid the image was.

On the weekend following the laboratory based assessment participants provided six

saliva samples at the following times: upon awakening, 40 minutes later, before lunch, at

3pm, before dinner, and before going to sleep. Analysis of the saliva can provide reliable

estimates of diurnal cortisol levels. Analyses involving cortisol will not be included as the

saliva has not yet been analyzed.

Intervention Procedures. Upon completion of this assessment women were randomly

assigned to either the relaxation training group or to the self care condition based on two

identical randomization schedules—one for high risk pregnancies and one for low risk

pregnancies since high-risk pregnancies increase the likelihood of pregnancy

complications and delivery complications. Risk-status of the pregnancy was based on

participant’s age, the existence of a medical condition known to impact the pregnancy

(e.g. hypertension), and consultation with the study obstetrician.

Participants randomized to the relaxation condition received six weeks of individual

relaxation training by graduate students who were supervised by a licensed clinical

psychologist. The first two sessions included training in the 16-muscle group version of

PMR; the third and fourth sessions, training in the 7-muscle group version of PMR; the

fifth session, training in the 4 muscle groups; and the final session involved the 4 muscle

group training in a recall format. The recall format does not involve tensing; rather, the

therapist brings the client’s attention to a muscle group and asks the client to recall what

it was like to release the muscle and just “let the muscle go” to become more and more

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deeply relaxed. At each session participants were also taught other relaxation methods

including diaphragmatic breathing, conditioned relaxation, how to identify stressful

thoughts, feelings, and behaviors, guided imagery, applied relaxation, cognitive

techniques, and differential relaxation to give the participants multiple methods for

achieving relaxation. Women were asked to practice PMR twice daily and to keep a daily

journal to record their practice sessions over the six weeks.

Those randomized to the self-care group received a handout titled “Ten Tips for

Dealing with Stress”, a list of suggestions for how to cope with stress and were

encouraged to use these coping strategies on a daily basis to reduce their stress. (Those in

the relaxation group also received this handout).

All participants completed post-treatment assessments at approximately seven weeks

after the first assessment (between 21 and 27 weeks gestation; “Time 2”) to assess the

psychological and physiological benefits of relaxation and again during the 3rd trimester

(between 34 and 36 weeks gestation; “Time 3”) to assess the longevity of those effects.

These follow up visits included the same questionnaires, physiological recordings and

tasks, and saliva sampling as the pre-treatment assessment. The follow up visits did not

include the Structured Clinical Interview Based on the Diagnostic and Statistical Manual

Fourth Edition (DSM-IV).

The study was approved by the Institutional Review Boards at both the University of

Arizona and the University of Virginia.

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Measures.

The following questionnaires are commonly used in studies examining the effects of

stress and anxiety on pregnancy outcome (see Table 1 for a summary).

Table 1. Summary of measures and timing of completion.

Type Name Who completed Timing of Measures

Perceived Stress Scale Edinburgh Depression Scale State-Trait Anxiety Scale Measures of

Mood The Depression, Anxiety, Stress Scale

Life Orientation Test-Revised (Optimism), Social Support Index Prenatal Life Events Scale The COPE

Moderators of Stress

State Relationships Questionnaires

Health Behaviors

Health Behaviors Questionnaire

MAMA (somatic symptoms of pregnancy)

Self-Care Practice

Items from COPE and Health Behaviors Questionnaire

Physiological Measures

Heart rate, respiratory sinus arrhythmia, skin conductance level, electromyography

All Participants

Times 1, 2, 3

Practice of Relaxation Training

Daily Diary of Relaxation Practice

Therapeutic Working Alliance Inventory

Relaxation Group Only

Treatment Phase (6 weeks)

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Alliance after Session 2

Obstetric Complications

Gestational Complications (vaginal bleeding, gestational diabetes, gestational hypertension, pre-eclampsia, eclampsia, placenta previa)

Intrapartum Complications (prolonged rupture membranes, premature delivery, induced labor, prolonged labor, use of forceps, Cesarean section)

Infant Measures (Birth weight, gestational age, Apgar scores at 1 and 5 minutes)

From Medical Records After Delivery

Measures of Mood. The Perceived Stress Scale (Cohen, Kamarck, & Mermelstein,

1983) is a 14-item questionnaire that measures the degree to which situations are

perceived as stressful. Items are rated on a 5-point scale from 0 to 4 and the total score is

the sum of the fourteen items.

The Edinburgh Depression Scale (Murray & Cox, 1990) is a 10-item measure

developed to assess symptoms of depression specifically for women in the postpartum

period. The measure has also been validated on pregnant women (Murray & Cox, 1990).

The severity of the symptoms is rated on a 4-point ranging from 0 to 3.

The State-Trait Anxiety Inventory (Speilberger et al., 1970) provides an index of both

trait and state levels of anxiety on a 40 item scale. Items are rated on a 4 point-Likert

scale ranging from never (1) to always (4).

The Depression, Anxiety, Stress Scale (Lovibond & Lovibond, 1995) is a 42 item self-

report inventory that yields 3 factors: Depression; Anxiety; and Stress. This measure

27

proposes that physical anxiety (fear symptomatology), mental stress (nervous tension and

nervous energy), and depression are three distinct factors.

Moderators of Stress. The Life Orientation Test-Revised (Scheier, Carver, & Bridges,

1994) is a 10-item measure assessing the degree of optimism. The items are rated on a 5-

point Likert-scale but only 6 of the 10 items are summed for a total score.

The Social Support Index (Collins et al., 1993) measures total received social support

as indicated by material aid, assistance with tasks, advice or information, and listening

while one expresses beliefs or feelings that occurred over the past seven days. The

participant indicates whether these types of support were received (Yes = 1 or No = 0)

and the degree of satisfaction with that support on a scale from not at all (1) to very much

(4). An overall summary score is derived by summing the number “Yes” responses to the

types of support, thus ranging from 0 to 4. An index of satisfaction with received support

was computed by taking the average, thus the index ranges from 0 to 4. Additionally the

following subscales are derived: social support from the baby’s father and from health

care providers and social network resources.

The Prenatal Life Events Scale (Lobel, Dunkel-Schetter, & Scrimshaw, 1992) is a 27-

item measure of stressful life events occurring during pregnancy. Participants rate

whether a stressful life event has occurred since the pregnancy began and how

undesirable/negative the event was on a 4-point scale ranging from not at all (0) to very

much (3). Two indices of stress are created: the number of events experienced are

summed and a mean distress score.

28

The COPE (Carver, Scheier, & Weintraub , 1989) assesses a number of coping

strategies people employ in response to stress. The COPE’s sixty items compose the

following scales: Positive reinterpretation and growth, mental disengagement, focus on

and venting of emotions, use of instrumental social support, active coping, denial,

religious coping, humor, behavioral disengagement, restraint, use of emotional social

support, substance use, acceptance, suppression of competing activities, and planning.

Marital satisfaction was measured with the State Relationships Questionnaire (Shoham

& Rohrbaugh, unpublished manuscript). The measure is composed of 24 items with 12

items in the positive and 12 in the negative to describe the current state of the

relationship, which form a Positive and a Negative Subscale.

Health Behaviors. The Health Behaviors Questionnaire has 27 items that measures

substance abuse, smoking, nutrition, and exercise (DeLuca & Lobel, 1995).

The Maternal Adjustment and Maternal Attitudes Scale (Kumar, Robson, & Smith,

1984) measures pregnant women’s perceptions of her body, somatic symptoms, the

marital relationship, attitudes to sex, and attitudes to the pregnancy and the baby. Only

the somatic symptoms (e.g. back pain, nausea) subscale will be examined.

Practice of Relaxation Methods. Participants in the relaxation group completed a daily

diary of when they practiced. Participants in the self-care group did not complete such a

diary.

Items from the COPE and from the Health Behaviors Questionnaire were used to

approximate the frequency with which participants practiced stress management skills, as

advised on the “Ten Tips for Reducing Stress” Handout that they all received upon

29

randomization. Items were standardized and a mean score was computed for a composite

variable, which will be referred to as “Self-Care Practice”.

Working Alliance Inventory. The Working Alliance Inventory (Horvath & Greenburg,

1986) assesses the degree to which the client and therapist perceive mutual agreement on

therapy goals, therapy tasks, and a strong personal bond. The Working Alliance

Inventory Short Form is a 12-item self-report assessment tool that can be used

interchangeably with the 36-item original version (Busseri & Tyler, 2003). Those

participants in the relaxation group and their therapists completed the questionnaires at

the end of sessions 2, 4, and 6; only session 2 data will be presented since data from the

subsequent sessions are more likely to be influenced by the participant’s perception of the

success of the treatment.

Gestational and Obstetric Complications. Medical charts were obtained to create an

index of the total number of complications during gestation and an index of the total

number of intrapartum (labor and delivery) complications. Gestational complications

include vaginal bleeding (occurring after randomization to treatment group), gestational

diabetes after the 20th week of pregnancy, gestational hypertension after the 20th week of

pregnancy, pre-eclampsia/eclampsia, and placenta previa (where the placenta partially or

fully covers the cervix). Intrapartum complications include prolonged rupture membranes

(a prolonged interval between the time the membranes rupture and the delivery),

premature delivery (before 37 weeks gestation), induced labor (due to abnormal labor

progress, fetal distress and/or prolonged gestation), prolonged labor greater than 21

30

hours, and delivery by forceps or Cesarean sections (not due to the large size of the baby

but due to fetal distress and/or abnormal labor progress.)

Infant Measures. Birth weight in grams, gestational age, and Apgar scores at 1 and 5

minutes were derived from the participants’ medical charts.

Physiological Measures. EMG and ECG amplified 2816 times with the Neuroscan

Synamps2 amplifier, with signals passed from 0 to 500 Hz. Physiological signals of Skin

Conductance and Respiration were recorded through the high level input of Neuroscan

Synamps2 with a DC amplifier, which passed signals from 0 to 500 Hz (1/2 amplitude

frequency). Skin Conductance was preamplified with iWorx’s GSR-200; Respiration was

derived directly with a piezoelectric signal sent to the Synaps high-level input. All of the

recording sites except for skin conductance activity and respiration, were abraded and

then cleaned with alcohol. Silver-silver-chloride electrodes were filled with conductance

gel prior to application on the skin. Electrode impedences for EMG and EKG were kept

below 10 KΩ. All sites were digitized at 2000 Hz.

Heart rate was recorded via electrodes placed on the right and left arm (Einthoven’s

Triangle Lead I) just below the elbow

A Compumedics Piezo Respiratory Effort Belt was placed around the chest of the

participant to measure respiration rate. This strain gauge contains a piezoelectric crystal

that changes electrical potential as it becomes deformed when the band stretches upon

inhalation.

Skin conductance activity was recorded by placing isotonic paste onto sensors strapped

onto the distal phalange of the index and pointer fingers on the participant’s non-

31

dominant hand. The surface area exposed on the fingers was kept constant for every

participant by using a collar with an 8 mm diameter.

Measurement of lateral frontalis muscle activity was recorded by placing two silver-

silver-chloride electrodes 1 centimeter apart from each other, 1 centimeter above the

upper border of the middle portion of the eyebrow on the non-dominant side, aligned

with the participant’s gaze. Muscle activity from the lateral gastrocnemius muscle (the

outer calf muscle) was recording by affixing the electrodes vertically 1 centimeter

distance from each other on the plateau of the muscle on both the left and right leg.

Physiological Data Reduction. Interbeat interval (IBI) series were derived from the

ECG series and were hand corrected for artifacts. Heart period variability in the high

frequency band (.12-.4 Hz) was extracted using CmetX software (Allen, 2002; Allen,

Chambers, & Towers, 2007). CmetX uses an optimal finite impulse response digital

filter, converts the IBI series to a time-series sampled at 10 Hz, filters the series using a

241-point optimal finite impulse response filter with half-amplitude frequencies of .12

and .40 Hz, and then takes the natural log of the variance of the filtered waveform as the

estimate of respiratory sinus arrhythmia (RSA). RSA is a measure of the amount of

variability in heart rate that can be attributed to the principal nerve of the parasympathetic

nervous system, the vagus nerve, commonly referred to as “cardiac vagal control”.

Respiration was recorded to verify that participants are breathing within the frequency

band assumed to reflect RSA, .12-.40 Hz. For those files where the respiration frequency

was outside of the respiration range of .12 to .40 files were visually inspected to ensure

that the respiration peak reflected respiration and not some other source (i.e. movement,

32

sensor placement, or drift). For those files that were visually inspected, the respiration

cycles for each minute were counted and the average number of cycles was calculated.

RSA for a given task was not included in statistical analyses when the respiration peak

was outside of the high-frequency range (i.e. a total of 8 files were excluded).

Skin conductance signals (SCL) were calibrated off-line. The independent Matlab

module ANSLAB (Wilhelm, 2006) was used to visually inspect and correct artifacts and

to derive mean skin conductance level (SCL) per condition.

Raw electromyography signals were filtered with a 12 Hz high pass filter and rectified.

The average rectified amplitude for each condition was obtained.

Statistical Analyses.

Repeated Measures ANOVAs were conducted to assess whether maternal mood and

physiological measures differed between groups across the three assessments. Chi-Square

compared the treatment groups in terms of gestational complications; Oneway ANOVAs

were conducted for intrapartum complications, total complications, and infant outcomes.

Post-hoc exploratory analyses, explained below in the results section, were conducted

to assess whether other psychological or physiological measures moderated the treatment

group or solely predicted psychological and birth outcomes.

33

RESULTS

Demographics

Eighty-eight percent of the sample was Caucasian, 4% African American, 4%

Hawaiian Native, and 4% Latina. The majority of the participants were married (88%)

with the rest of the sample either living separately from or together with the partner or

divorced. The mean age of the participants was 29 years old (st. dev = 4.4) with a range

of 22 to 39. On average women were in their 16th week of pregnancy (st. dev = 2.2) when

they completed the diagnostic interview. Sixty-five percent of the sample met criteria for

a history of one or more mental disorders. These disorders included Major Depression

(39%), Substance Abuse (12%), Specific Phobia (15%), Posttraumatic Stress Disorder

(8%), Anxiety Disorder NOS (4%), Anorexia Nervosa (4%), Bulimia Nervosa (4%) and

Binge Eating Disorder (4%).

Specific Aim One

Feasibility of Providing Relaxation Training to Highly Stressed Pregnant Women.

Approximately five women per month called to inquire about the study with nearly half

of those women meeting eligibility criteria. Fifteen percent of the participants dropped

out from the study: two dropped out after the initial diagnostic interview; one dropped out

from the relaxation group; and one, from the self-care group. Three of these women

dropped out due to the time commitment required for participating in the study and one

of the women was advised by her obstetrician to minimize the stress in her life to prevent

34

pregnancy complications from occurring1. One woman had a late-term miscarriage prior

to beginning the treatment phase of the study. One woman in the self-care group did not

comply with the self-care protocol and instead began taking anti-depressant medications

during the treatment phase of the study.

Reduce Negative Mood in Stressed Pregnant Women. Analyses excluded data from

the participant who miscarried and the participant who was treated with anti-depressant

medications. Two women only completed the diagnostic interview prior to dropping out

of the study. Thus, 10 women from the relaxation group and 12 from the self-care were

included in the following analyses.

Repeated measures ANOVA with main effects of time and treatment group and their

interaction indicated no differences between treatment groups in any of the mood

questionnaires across the three laboratory assessments (see Table 2 for means, standard

deviations). Similar analyses revealed no differences between treatment groups in terms

of reducing somatic symptoms of pregnancy (e.g. nausea) or changing the frequency of

engaging in healthy behaviors (e.g. exercise, sleep; all p’s >.16)

Table 2: Means and standard deviations for the main outcome measures of stress, depression, and anxiety. Relaxation Group Self-Care Group

Measure Mean (s.d.) Mean (s.d.) Perceived Stress Scale * Time 1 28.0 (5.2) 30.1 (7.7) Time 2 23.2 (6.3) 25.6 (8.0) Time 3 23.9 (7.0) 21.9 (6.8) DAS_Stress Subscale Time 1 13.1 (4.5) 15.1 (5.3) Time 2 12.4 (7.9) 15.0 (6.0) Time 3 13.8 (8.3) 11.6 (6.8) DAS_Depression Scale Time 1 2.5 (3.0) 5.4 (4.5) 1 Irony noted.

35

Time 2 3.3 (2.1) 4.6 (6.3) Time 3 4.1 (2.8) 3.0 (1.5) EDS Time 1 7.2 (3.3) 8.7 (3.8) Time 2 7.1 (2.5) 8.0 (4.7) Time 3 6.9 (3.5) 6.1 (2.8) State Anxiety Inventory Time 1 39.6 (7.5) 38.9 (11.2) Time 2 40.9 (11.1) 37.0 (8.5) Time 3 36.9 (7.1) 33.1 (3.9) Trait Anxiety Inventory Time 1 40.9 (4.0) 44.0 (6.7) Time 2 39.9 (5.3) 41.1 (5.8) Time 3 38.1 (4.7) 38.4 (5.3) DAS_Anxiety Scale Time 1 3.3 (4.2) 4.3 (5.3) Time 2 5.4 (6.1) 2.7 (2.5) Time 3 7.6 (6.7) 1.7 (1.2) Note: *=significant difference at p = .01 in measures across time. Although there was a significant time effect for change in stress over the course of pregnancy, in no case was there a Time x Treatment Group Interaction (all p’s >= .20).

To examine whether the frequency of practicing relaxation methods in the relaxation

group and the frequency of Self-Care Practice for both groups could predict stress,

anxiety, or depression at the post-treatment assessments, Pearson’s bivariate correlations

were computed. For those variables related to the frequency of practice, linear regressions

were conducted to predict the post-treatment symptom with the average weekly

frequency of relaxation practice after accounting for the pre-treatment symptom. One

participant was excluded from these analyses as Cook’s Distance indicated the frequency

of practice was a significant outlier that greatly influenced the relationship between

frequency of relaxation practice and each symptom.

In the relaxation group, the average weekly practice of relaxation predicted scores at

Time 2 on the Perceived Stress Scale and at Time 3 on the Perceived Stress Scale, the

EDS, and the State Anxiety Inventory (semi-partial r’s ≥ -.53, p’s ≤ .06; see Table 3 and

36

Figure 1.) By contrast, in the Self-Care group, the frequency of Self-Care Practice was

unrelated to stress, anxiety, or depression at any time point for the self-care group

(p≥.12).

Table 3. Ranges, semi-partial r’s, and significant F-change from regression that predicted post-treatment symptoms from the frequency of relaxation practice after accounting for the baseline symptom.

Dependent Measure Semi-partial r Significant F-Change

Perceived Stress Scale Time 2 -.73 .03 Perceived Stress Scale Time 3 -.88 .00 EDS Time 3 -.79 .00 State Anxiety Inventory Time 3 -.53 .06 Note: In each regression the baseline symptom measure was entered into step 1 of the regression with average weekly relaxation practice entered at step 2. The semi-partial r2 reflects the additional variance accounted for by the weekly relaxation practice beyond that accounted for by baseline symptoms. Semi partial r rather than r2 is presented here to show direction of effect. EDS: Edinburgh Depression Scale

37

Figure 1. Average frequency of relaxation practice per week and unstandardized residuals of A) Perceived Stress Scale at Time 2, B) Perceived Stress Scale at Time 3, C) Edinburgh Depression Scale (EDS) at Time 3 and D) State Anxiety Inventory at Time 3.

Average Frequency of Relaxation Practice Per Week

7.006.005.004.003.00

Un

sta

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10.00

5.00

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R Sq Linear = 0.631

Average Frequency of Relaxation Practice Per Week

7.006.005.004.003.00

Un

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15.00

10.00

5.00

0.00

-5.00

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R Sq Linear = 0.917

Average Frequency of Relaxation Practice Per Week

7.006.005.004.003.00

Un

sta

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of

ED

S a

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ime

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6.00

4.00

2.00

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R Sq Linear = 0.955

Average Frequency of Relaxation Practice Per Week

7.006.005.004.003.00

Un

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R Sq Linear = 0.582

38

The same two step process of examining bivariate correlations followed by regressions

were conducted to examine whether the working alliance subscales (client- and therapist-

rated task, goal, and bond) between the participant and therapist could predict levels of

stress, anxiety, and depression. The degree to which the client believed she and the

therapist were working towards a common goal predicted the level of depression, as

measured by the DAS at Time 2. Therapist-rated bond and therapist-rated task predicted

the level of depression as measured by the DAS and EDS, respectively. Therapist-rated

task predicted the level of stress as measured by the Perceived Stress Scale (see Table 4

and Figure 2). No other significant relationships were found.

Table 4 Ranges, semi-partial r’s, and significant F-change from regression that predicted post-treatment symptoms from the subscales of the Working Alliance Inventory after accounting for the baseline symptom.

Dependent Measure Step 2 Variable Semi-partial r

Significant F-Change

DAS_Depression Scale Time 2 Client-Rated Goal -.69 .03 DAS_Depression Scale Time 2 Therapist-rated

Bond -.72 .02

EDS Time 3 Therapist-rated Task -.63 .03 Perceived Stress Scale Time 3 Therapist-rated Task -.72 .01 Note: In each regression the baseline symptom measure was entered into step 1 of the regression with average weekly relaxation practice entered at step 2. The semi-partial r2 reflects the additional variance accounted for by the Working Alliance Inventory subscales beyond that accounted for by baseline symptoms. Semi partial r rather than r2 is presented here to show direction of effect. EDS: Edinburgh Depression Scale; DAS: Depression Anxiety Stress Scale.

39

Working Alliance Inventory Client-Rated Goal at Session 2

28.0026.0024.0022.00

4.00

3.00

2.00

1.00

0.00

-1.00

-2.00

-3.00

R Sq Linear = 0.312

Nonsta

ndard

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Subscale

at T

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Working Alliance Inventory Therapist-Rated Bond at Session 2

28.0026.0024.0022.00

4.00

3.00

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0.00

-1.00

-2.00

-3.00

R Sq Linear = 0.619

Nonsta

ndard

ized R

esid

ual of

ED

S a

t T

ime 3

Working Alliance Inventory Therapist-Rated Task at Session 2

28.0026.0024.0022.0020.00

6.00

4.00

2.00

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-2.00

-4.00R Sq Linear = 0.66

Nonsta

ndard

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Working Alliance Inventory Therapist-Rated Task at Session 2

28.0026.0024.0022.0020.00

15.00

10.00

5.00

0.00

-5.00

-10.00R Sq Linear = 0.55

Figure 2. Working Alliance Inventory Subscale and unstandardized residuals: A) DASS Depression Scale at Time 2, and Client-Rated Goal B) DASS Depression Scale at Time 2 and Therapist-Rated Bond, C) Edinburgh Depression Scale (EDS) at Time 3 and Therapist-Rated Task, and D) Perceived Stress Scale at Time 3 and Therapist-Rated Task.

40

Specific Aim Two

Birth Outcomes. Seventy-four percent of the women in the study experienced one or

more complications during pregnancy, labor, or delivery. Twenty-two percent

experienced a gestational complication and 70% experienced an intrapartum

complication (see Table 5). Groups did not differ in frequency of gestational

complications (Pearson Chi-Square = .10, p=.75), intrapartum complications

(F[1,20]=.84, p=.37), or total complications (F[1,20]=.88, p=.36). Treatment group failed

to predict gestational age at birth, birth weight, or Apgar score at 1-minute (all p’s ≥ .20.)

The infants of the self-care group had a statistically significant higher score on the Apgar

at 5-minutes than the infants of the relaxation group (F[1,20]=6.85, p=.02).

Table 5. Frequency of complications per treatment group and infant measures Complication Relaxation

n=10 Self-Care

n=12 Gestational Complications, Total % 20% 23%

Gestational diabetes 2 0 Gestational Hypertension 0 1

Pre-eclampsia 0 1 Eclampsia 0 0

Placenta previa 0 1 Intrapartum complications 70% 70%

Premature Delivery 2 1 Prolonged rupture membranes 0 2

Induced labor 5 5 Prolonged labor (greater than 21 hours) 1 2

Delivery by forceps 1 0 Delivery by Cesarean 4 3

Relaxation Self-Care Infant Measures Mean (s.d.) Mean (s.d.)

Gestational age at birth 38.4 (2.5) 39.5 (1.4) Birth weight (grams) 3231.7 (695.2) 3561.8 (529.3)

Apgar score at 1 minute 7.8 (1.3) 8.0 (1.1) Apgar score at 5 minutes 8.5 (0.7) 9.1 (0.3)

41

To examine whether the frequency of practicing relaxation methods in the relaxation

group and the frequency of Self-Care Practice for the self-care group could predict

intrapartum complications, total complications, infant weight, and gestational age at birth,

Pearson’s bivariate correlations were computed. A one-way ANOVA examined whether

there was a difference in the frequency of practicing relaxation methods in the relaxation

treatment group in those who did and did not experience gestational complications.

In the relaxation group, the frequency of practicing relaxation methods was

significantly different between those who did and did not have a gestational complication

(F[1,6]=9.78, p=.02; see Figure 3). Frequency of practicing relaxation methods did not

predict any other pregnancy related outcomes (p’s >.41). Self-care Practice did not

predict any pregnancy related outcomes in the self-care group (all p’s ≥ .15).

Figure 3. The average frequency of practicing relaxation methods in the relaxation treatment group for those who did and did not experience a gestational complication.

Av

era

ge

Fre

qu

en

cy

of

Re

lax

ati

on

Pra

cti

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pe

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k

3.50

5.68

Gestational Complications

YesNo

6.00

5.00

4.00

3.00

2.00

1.00

0.00

42

Exploratory Aim

Physiological Changes. Results from the visualization, relaxation, and final recovery

tasks did not produce robust physiological responses and were therefore not considered

further in the following analyses.

To simplify analyses, physiological signals across the two stress tasks (serial

subtraction and the Stroop Task) were averaged to one variable called “Stress Tasks” and

the two subsequent recovery periods were averaged to one variable called “Recovery”.

To examine whether the stress tasks were physiologically arousing, repeated measures

ANOVAs were conducted within each assessment between Stress Tasks and Recovery.

Significant differences between Stress Tasks and Recovery were revealed at each

assessment, with Stress Tasks showing higher heart rate (all p’s <.08), lower RSA (all p’s

<.01), higher SCL except for Time 3 where SCL did not change (all p’s <.03), higher

right leg gastrocnemius EMG at Time 1 and no change at Time 2 or 3 (all p’s <.01) and

higher left leg gastrocnemius EMG at Time 1 but not at Times 2 or 3 (all p’s <.00, except

p=ns for Time 2), and higher Frontalis EMG (all p’s < .01). Similarly, Repeated

Measures ANOVA revealed a main effect in time such that participants consistently rated

the stressful tasks as more stressful than the recovery periods over time (F[1,14]=23.6,

p<.001). There were no main effects for treatment group or a time by treatment group

interaction effect for any physiological signal.

One-way ANOVAs were conducted to examine baseline differences between groups

in heart rate, RSA, SCL, and EMG in the legs and face. No group differences were

revealed in any of the resting signals at any assessment during pregnancy (see Table 6).

43

Table 6: Means and standard deviations of the physiological signals during tasks across time.

Relaxation Group Self-Care Group Measure Resting Stress

minus Resting

Recovery minus

Resting

Resting Stress minus

Resting

Recovery minus

Resting Heart Rate a

Time 1 82.3 (14.1) 2.8 (2.5) 0.5 (2.5) 81.2 (7.7) 4.4 (3.9) 0.5 (2.4)

Time 2 85.2 (12.2) 1.3 (3.5) -1.3 (3.6) 83.9 (10.8) 2.5 (2.2) -0.5 (1.3) Time 3 87.9 (10.3) 2.2 (4.5) 0.6 (2.9) 89.0 (11.4) 1.1 (3.3) -0.2 (2.4)

Recovery

RSA a Time 1

6.2 (1.0) -0.9 (0.9) -0.4 (0.6) 6.2 (0.9) -0.5 (0.6) -.1 (0.4)

Time 2 5.7 (1.1) -0.6 (0.7) 0.1 (0.8) 5.5 (1.0) -0.5 (0.7) 0.1 (0.2) Time 3 5.9 (1.0) -1.1 (0.7) -0.2 (0.5) 5.4 (1.1) -0.6 (0.4) -0.2 (0.5)

SCL a

Time 1 2.8 (1.5) 0.1 (0.8) -0.4 (0.8) 2.0 (1.0) 0.0 (0.9) -0.6 (0.9)

Time 2 1.1 (1.8) 0.1 (0.9) -0.1 (1.3) 1.5 (0.7) 0.3 (0.7) -0.3 (0.6) Time 3 3.9 (3.5) -0.1 (1.2) -0.9 (0.8) 2.1 (1.4) 0.0 (0.8) -0.5 (0.9)

LF EMG

Time 1 0.4 (1.0) 0.6 (1.5) -0.9 (1.0) 0.2 (0.9) 0.8 (1.2) -0.6 (0.8)

Time 2 0.1 (1.1) 1.1 (1.4) -0.4 (1.1) 0.3 (0.9) 0.7 (1.3) -0.7 (0.9)

Time 3 0.2 (1.0) 1.0 (1.3) -0.6 (1.0) 0.7 (1.2) 0.0 (1.7) -1.1 (1.2)

LG EMG Time 1

0.3 (1.4) 0.2 (1.7) -0.6 (1.6) -0.1 (0.2) 0.3 (0.5) 0.0 (0.2)

Time 2 0.1 (0.3) -0.1 (.43) -0.2 (0.5) 0.1 (0.3) -0.0 (0.4) -0.1 (0.4)

Time 3 0.4 (0.6) -0.3 (0.6) -0.4 (0.7) 0.4 (0.8) -0.4 (0.8) -0.5 (0.9)

RG EMG a b c Time 1

0.2 (1.6) 0.6 (1.7) -0.3 (1.7) 0.5 (0.9) 0.3 (1.1) -0.7 (0.9)

Time 2 1.3 (0.4) -1.0 (0.5) -1.6 (0.4) 1.3 (0.9) -0.9 (1.3) -1.4 (1.0)

Time 3 1.3 (0.6) -0.9 (0.8) -1.3 (0.7) 1.1 (1.2) -0.8 (1.5) -1.3 (1.1) Note: a=significant difference in resting measures across time, p<.06. b= significant differences in stress tasks over time, p<.01. c= significant differences in recovery over time, p<.01. Although there were significant time effects, in no case was there a Time x Treatment Group interaction (all p’s >= .20). SCL = Skin Conductance Level; LF EMG = Lateral Frontalis Electromyography; LG EMG = Left Gastrocnemius EMG; RG EMG = Right Gastrocnemius EMG.

44

Repeated measures ANOVAs were conducted to examine whether there were differences

across pregnancy and between groups in physiology during resting, stress tasks, and

recovery. Main effects of time were found across the pregnancy such that resting heart

rate increased, (F[1,16]=13.0, p=.00), resting RSA decreased, (F[1,16]=5.6, p<.01),

resting SCL increased (F[1,16]=3.13, p=06), resting right gastrocnemius EMG increased

(F[1,16]=5.8, p<.05), right leg gastrocnemius EMG during stress tasks decreased

(F[1,16]=8.5, p<.01), and right leg gastrocnemius EMG during recovery decreased

(F[1,16]=5.4, p<.01). No changes in Lateral Frontalis EMG or left leg gastrocnemius

were found. No main effects for treatment group or time by treatment group interaction

effects were revealed.

Psychological Predictors of Birth Outcomes and Infant Variables. Based on previous

research findings (Orr et al, 2007; Lobel et al, 2000; Rin et al, 1999; Collins et al, 1993;

Feldman et al, 2000; Norbeck & Tilden, 1983) analyses were conducted to examine

whether any of the following demographic and psychological variables were related to

birth outcomes: maternal age and social support, prenatal life events, optimism, marital

satisfaction, or negative mood all at Time 1 (a composite variable for negative mood was

created by computing the average standardized value for the EDS, STAI, and Perceived

Stress Scale as suggested by Lobel et al, 2000). Analyses did not include smoking or

substance use as covariates as all women in the study denied use of those substances.

Separate Oneway ANOVAs revealed a trend whereby those women who experienced a

gestational complication had greater negative mood at Time 1 (F[1,20]=3.33, p=.08; See

45

Figure 4). None of the variables differentiated women who did and did not experience an

intrapartum complication.

Figure 4. The difference in the level of negative mood between those women who

experienced a gestational complication versus those who did not.

Ne

ga

tiv

e M

oo

d a

t T

ime

1

Gestational Complications

YesNo

0.592

-0.132

0.60

0.40

0.20

0.00

-0.20

Bivariate correlations were conducted to examine whether maternal age and social

support, prenatal life events, optimism, marital satisfaction, or negative mood at Time 1

predicted infant outcomes of infant’s gestational age, weight, and Apgar scores at 1 and 5

minutes. Although infant weight and apgar scores were statistically related to several

variables, examination of the scatterplot and confirmation via Cook’s distance revealed

several outliers accounting for the correlations. No significant relationships were

revealed.

46

Physiological Moderators and Predictors of Outcome. Previous research has found

baseline RSA to interact with treatment in predicting less severity of symptoms in

uncomplicated bereavement (O’Connor, Allen, & Kaszniak, 2005) and fewer health

complaints and depression (Sloan & Epstein, 2005). General Linear Models with Type I

Sum of Squares were conducted to examine whether resting RSA at Time 1 moderated

treatment in the prediction of post-treatment stress, anxiety, and depression after first

accounting for baseline symptom. Indeed, resting RSA interacted with treatment group to

predict trait anxiety at Time 2 (F[1,17] = 3.7, p=.07; see Figure 5) such that resting RSA

at Time 1 in the relaxation group but not in the self-care group was related to trait anxiety

at Time 2. Resting RSA at Time 1 did not predict any other symptom at any other time.

Figure 5. Resting RSA at Time 1 predicted trait anxiety at Time 2 for those in the relaxation treatment group (semi-partial r = .57) but not for those in the self-care group.

47

Collapsing across subjects to examine Time 3 outcomes, bivariate correlations

followed by Linear Regressions examined whether resting RSA at Time 1 independently

predicted post-treatment symptoms of stress, anxiety, and depression after accounting for

baseline symptoms. Resting RSA predicted depression using both the DAS and EDS,

state and trait anxiety, and stress as measured by the perceived stress scale (see Table 7

and Figure 6).

48

Table 7. Ranges, semi-partial r’s, and significant F-change from regression that predicted post-treatment symptoms from baseline RSA after accounting for the baseline symptom.

Dependent Measure at Time 3 Semi-partial r Significant F-Change

DASS_Depression Scale -.75 .00 EDS -.44 .04 State Anxiety Inventory -.54 .01 Trait Anxiety Inventory -.58 .00 Perceived Stress Scale -.39 .06 Note: In each regression the baseline symptom measure was entered into step 1 of the regression with baseline Respiratory Sinus Arrythmia (RSA) entered at step 2. The semi-partial r2 reflects the additional variance accounted for RSA subscales beyond that accounted for by baseline symptoms. Semi partial r rather than r2 is presented here to show direction of effect. EDS: Edinburgh Depression Scale; DASS: Depression Anxiety Stress Scale.

49

Resting RSA at Time 1

8.007.006.005.00

6.00

4.00

2.00

0.00

-2.00

-4.00R Sq Linear = 0.576

Un

sta

nd

ard

ized

Re

sid

ua

ls o

f D

AS

De

pre

ss

ion

Sc

ale

at

Tim

e 3

Un

sta

nd

ard

ized

Resid

uals

of

ED

S a

t T

ime 3

Resting RSA at Time 1

8.007.006.005.00

5.00

2.50

0.00

-2.50

-5.00

-7.50R Sq Linear = 0.25

Un

sta

nd

ard

ized

Resid

uals

of

SA

I at

Tim

e 3

Resting RSA at Time 1

8.007.006.005.00

10.00

5.00

0.00

-5.00

-10.00

R Sq Linear = 0.407

Un

sta

nd

ard

ized

Resid

uals

of

TA

I at

Tim

e 3

Resting RSA at Time 1

8.007.006.005.00

10.00

5.00

0.00

-5.00

-10.00R Sq Linear = 0.432

Un

sta

nd

ard

ized

Resid

uals

of

Perc

eiv

ed

Str

ess S

cale at

Tim

e 3

Resting RSA at Time 1

8.007.006.005.00

15.00

10.00

5.00

0.00

-5.00

-10.00

-15.00

R Sq Linear = 0.203

Figure 6. Resting baseline respiratory sinus arrhythmia (RSA) and unstandardized residuals of Time 3: A) DAS Depression Scale, B) Edinburgh Depression scale (EDS), C) State Anxiety Inventory (SAI), D) Trait Anxiety Inventory (TAI), and E)Perceived Stress Scale

50

Oneway ANOVA examined whether those women with and without complications had

different levels of RSA. A statistical trend suggested that those women who experienced

a gestational complication during pregnancy were more likely to have lower resting RSA

at Time 1 than those women who did not experience gestational complications

(F[1,20]=3.18, p=.09; See Figure 7). There were no such differences in resting RSA at

Time 1 in women who had intrapartum complications (F[1,20]=.17, p=ns) and bivariate

correlations indicated no relationships between resting RSA at Time 1 and infant

outcomes (p’s > .18).

Figure 7. Group differences in resting RSA at Time 1 in women who did and did not experience gestational complications.

Resti

ng

RS

A a

t T

ime 1

Gestational Complications

YesNo

5.47

6.336

6.00

4.00

2.00

0.00

51

DISCUSSION

Feasibility.

The first aim of the study was to determine the feasibility of running a treatment study

that involved stressed pregnant women. Although recruitment was slower than

anticipated (i.e. anticipated four women per month; in reality, two eligible women per

month) recruitment rates might be faster with more research staff and in a larger city than

Charlottesville, Virginia whose population, including the surrounding area was

approximately 118,000 according to the 2005 census.

The dropout rate was low at 15%--which is half the typical rate found in outpatient

psychotherapy treatment studies (Bados, Balaguer, & Saldana, 2007)--with equal

numbers of women dropping out of both randomization groups. In terms of adherence to

the treatment protocol, all but one woman from the self-care group adhered to the

constraints of the study of not engaging in psychotherapy or taking anti-depressant

medication. In the relaxation group although therapists recommended that the women in

the relaxation group practice PMR at least once a day but preferably twice a day, the

mean frequency of practice per week was 5.7 (s.d. = 2.0). It is worth noting, however,

that a repeated measures ANOVA revealed that the frequency of practicing PMR

increased over the course of the training sessions (F[2,7]=3.0, p=.03). Post-hoc pairwise

comparisons indicated a significant increase in relaxation practice in the second and third

weeks in comparison to the other weeks (p’s <.05). Based on the author’s experience

working with the participants, nearly every participant indicated a feeling of dread when

having to practice the 16-muscle version of PMR in the first week. At the second session

52

participants were reminded that they needed to practice the long version for only one

more week before they would learn a shorter version. After this “pep talk” and after

learning the shorter version, practice frequency increased.

Overall, the feasibility of the study is good. Future studies similar to this protocol

could incorporate a motivational enhancement protocol (Miller & Rollnick, 2002) at the

beginning of the relaxation training protocol in an attempt to increase relaxation practice

and repeat the importance of practicing PMR twice a day.

Relaxation as an Intervention for Reducing Negative Mood.

Relaxation training was not more effective than self-care instructions in reducing

negative mood in highly stressed pregnant women. In fact there were no changes in mood

over time, except for a reduction in self-reported stress as evidenced by a 6-point change

on the Perceived Stress Scale.

Several analyses, however, suggest relaxation training has the potential for reducing

negative mood in stressed pregnant women. Those women in the relaxation group who

practiced more frequently had greater reductions in stress post-treatment and in the third

trimester, and in third trimester state anxiety and depression. It is perplexing that

depression and anxiety were not reduced at Time 2; perhaps these symptoms require

more time before the relaxation training has an impact. Supporting this hypothesis a

meta-analysis by Carlsen et al (1993) suggests that PMR’s impact on psychological

outcome increases over time. Further, PMR is more effective with more training sessions,

which likely asymptotes at 12 sessions.

53

Consistent with the treatment literature (Beutler, Malik, Alimohamed, Harwood,

Talebi, Noble, et al, 2004) the therapeutic relationship between the therapist and the

participant also accounted for depression at Time 2 and 3 and perceived stress at Time 3.

The design of the study does not permit parsing out whether the relaxation practice or the

therapeutic relationship accounted for more of the variance in symptom outcome.

Last, RSA moderated treatment such that those women in the relaxation group with

greater RSA had less trait anxiety at Time 2 than similar women in the self-care group.

Taking these three findings together, the present study suggests that with greater

adherence to practice, relaxation training during pregnancy holds potential efficacy in the

treatment of negative mood. Alternatively, there is the possibility that a third unmeasured

factor might account for these findings? More research is clearly needed.

Relaxation as an Intervention for Reducing Complications During Pregnancy.

Seventy-four percent of the women in the study experienced one or more

complications over the course of pregnancy or during labor and delivery, which is

slightly greater than the rates of complications reported in other studies involving highly

stressed pregnant women (Clifford et al, 1989; Da Costa et al, 1998; Norbeck et al 1983).

Although the treatment groups did not differ in terms of the rates of complications, again,

those women in the relaxation group who practiced more often were less likely to

experience a gestational complication; there was no relationship with intrapartum

complications. It is not clear why relaxation training would impact gestational

complications to the exclusion of intrapartum complications. One hypothesis involves the

timing of the intervention. The women practiced the relaxation methods throughout the

54

second trimester, shortly before gestational complications tend to occur in the third

trimester. Relaxation training did not continue in the 3rd trimester and women were not

required to monitor their practice in the 3rd trimester. Perhaps without the therapist’s

pressure to continue practicing, women discontinued their practice and the effects of

relaxation training were too distal to impact the course of labor and delivery, or on

gestational age or birth weight, for that matter. On the other hand, while research has

documented relaxation training’s impact on the HPA Axis, the immune system, and

autonomic nervous system—systems implicated in affecting the development of

gestational diabetes, hypertensive disorders, and the start of premature labor—it isn’t

clear how these mechanisms would impact the progression of labor, once it started, and

the use of cesarean delivery or forceps.

The infants of the self-care group had a statistically significant difference in Apgar

scores at 5 minutes postpartum. The clinical significance of this difference is

questionable. The APGAR is an evaluation of an infant’s activity (muscle tone), pulse

(heart rate), grimace (reflex irritability), appearance (skin color), and respiration (rate and

effort). An infant of a score of 7 or above in considered in good health. Neither group

scored below a 7 on the Apgar at 5-minutes and the mean difference between groups was

less than a .5 difference.

Physiological changes over pregnancy.

Despite the success of the stress tasks to elicit changes in arousal, relaxation training

did not impact any measured physiological signals at rest, in response to the stressful

tasks, or during recovery. This study replicated DiPietro and colleagues’ (DiPietro et al,

55

2005) findings that RSA decreased and SCL increased from 2nd to 3rd trimesters and adds

the finding of an increase in resting emg from the right gastrocnemius muscle over the

pregnancy, during the stressful tasks, and during recovery. This increase in emg in the

right leg might be due to the increased weight being carried by the legs. Why the left leg

did not similarly respond is a mystery. This might reflect a majority of right leg

dominance in this sample.

Independent Predictors of Outcome.

Negative mood at Time 1 predicted gestational complications but not intrapartum

complications. This finding conforms with Clifford et al (1989) who found that state

anxiety at 16 weeks but not later in the pregnancy predicted the incidence of any

gestational or intrapartum complication. Da Costa et al (1998) found the opposite, such

that women who experienced anxiety in the 2nd and 3rd trimesters were more likely to

have a gestational complication than those women who experienced an intrapartum or no

complication. Further research with larger sample sizes will need to tease apart the

relevance of the timing of the mood disturbance on the pregnancy outcomes.

More surprising is the lack of predictive power of age, optimism, and social support,

as these variables are consistently related to infant variables, like birth weight (Collins et

al, 1993; Feldman et al, 2000, Lobel et al, 2000; Rini et al, 1999). The participants in the

current study were more educated and wealthier than those in previous studies. The

majority of women who participated in the study had at least a bachelors degree, had a

household income of $50,000 or more, and reported fairly large social networks and

resources.

56

This is the first study to date to examine cardiac vagal control (CVC), measured by

RSA, as a potential buffer against the negative impact of stress during pregnancy. Resting

RSA at Time 1 predicted less Time 2 state anxiety for the relaxation group but not for the

self-care group and greater RSA independently predicted less depression, anxiety, and

stress at Time 3 and fewer gestational complications for the entire sample. CVC is

purported to reflect the flexibility of an organism to respond to environmental stressors

(Friedman, 2007) and emotion regulation capabilities (e.g. Porges, 2007). Women with

greater CVC might have greater capabilities to cope with the seemingly limitless stressors

associated with pregnancy and relaxation training might make it easier to cope sooner

than those who did not receive such training.

Cardiac vagal control might confer fewer gestational complications because of CVC’s

effect on the body. As Masi et al (2007) describe, lower CVC is related to elevated

glucose in diabetics, higher blood pressure, greater catecholamine release from

sympathetic nerve endings, and promotes the immune system’s inflammatory response.

Future Directions.

The results of this pilot study suggest a larger study is warranted to further explore

the impact of relaxation training on negative mood during pregnancy and on

complications during pregnancy, labor, and delivery. The study could be designed to

examine the unique variance associated with relaxation training and therapeutic alliance

between therapist and client. To increase symptom reduction more relaxation sessions

could be added with follow-up sessions included in the 3rd trimester to promote

continuing practice of the methods. Based on feedback from relaxation participants, a

57

group format could be included that would focus on stressful issues unique to pregnancy

(i.e. body image, marital relationship, changing identity) and facilitate social support with

other pregnant women.

58

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