2012. Vol.3, Special Issue, 782-786
Published Online September 2012 in SciRes (http://www.SciRP.org/journal/psych) http://dx.doi.org/10.4236/psych.2012.329118
Copyright © 2012 SciRes.
Yoga Reduces Prenatal Depression Symptoms
Jennifer Mitchell1, Tiffany Field1,2*, Miguel Diego2, Debra Bendell1, Rae Newton1,
1Fielding Graduate University, Santa Barbara, USA
2Touch Research Institute, University of Miami Medical School, Miami, USA
3Florida International University, Miami, USA
Received June 28th, 2012; revised July 29th, 2012; accepted September 1st, 2012
This research assessed the effects of yoga on prenatal depression symptoms using archival data. De-
pressed pregnant women were randomly assigned to either a yoga treatment group (n = 12) or a parenting
education control group (n = 12). Women in the yoga group participated in classes two times a week for a
period of 12 weeks. The attention control group received 12 parenting education sessions on the same
schedule. The yoga versus control group showed greater decreases on the depressed affect and somatic/
vegetative subscales and the summary score of the Center for Epidemiological Studies Depression Scale.
Thus, yoga appears to reduce depression symptoms in pregnant women.
Keywords: Yoga; Prenatal Depression Symptoms
Estimates of the prevalence of prenatal depression span from
11% (Frisch & Riecher-Rössler, 2010) to 26% (Kim et al.,
2006). Sub-clinical levels of depression have been noted in as
many as 20% to 49% of pregnant women (Orr, Blazer, & James,
2006). Ethnic minorities are considered a higher risk group
(Gavin, Melville, Rue, Guo, Dina, & Katon, 2011), with ap-
proximately 25% of women reporting clinical levels of depress-
sive symptomatology (Edge, 2007). In addition, a number of
psychosocial factors can increase a woman’s relative risk, in-
cluding having a low income and being unmarried (Lancaster,
Gold, Flynn, Yoo, Marcus, & Davis, 2010; Vesga-Lopez,
Blanco, Keyes, Olfson, Grant, & Hasin, 2008). Prenatal depres-
sion may also go unreported by women and be overlooked by
doctors due to the overlap of symptoms with common physical
complaints of pregnancy (Melville, Gavin, Guo, Fan, & Katon,
Prenatal depression affects both mother and child. One of the
most serious outcomes is premature birth, and prenatal depress-
sion is considered a serious risk factor for prematurity (Dayan
et al., 2006; Field, Diego, Hernandez-Reif, Deeds, Holder et al.,
2009; Orr et al., 2006). Prematurity accounted for 12% of births
in the United States in 2008, reflecting an increasing trend since
1981 (Martin, Osterman, & Sutton, 2010). Most notably, pre-
maturity is the primary reason for infant mortality and is asso-
ciated with a number of adverse health and development risks
(Center for Healthcare Research & Transformation, 2010; Field,
Diego, Dieter et al., 2004).
Prenatal depression can also have long-term effects on the
development of the child.
Prenatally depressed mothers have delivered infants who had
higher cortisol levels and lower dopamine and serotonin levels,
as well as lower birthweight and gestational ages (Field, Diego,
Dieter et al., 2004). Negative birth and early childhood out-
comes associated with prenantal depression include diminished
responsivity to stimulation (Field, Diego, & Hernandez-Reif,
2009; Field, Hernandez-Reif, & Diego, 2011), and poorer per-
formance on neonatal assessments (Field, Diego, & Hernandez-
Reif, 2010). One area of particular concern is the decreased re-
sponsivity by both mother and child within the first six months,
which can lead to increased infant distress (Field, 2011a).
These negative interactions between mother and child early in
life can have serious implications for attachment (Weinfield,
Sroufe, Egeland, & Carlson, 2008). Additional negative effects
of prenatal depression on child development include disrupted
sleep patterns (Field, Diego, Dieter et al., 2004), behavior prob-
lems (de Bruijn, van Bakel, & van Baar, 2009), developmental
delays (Deave, Heron, Evans, & Emond, 2008), and increased
violence in adolescents (Hay, Pawlby, Waters, Perra, & Sharp,
2010). Moderate pressure massage therapy has decreased pre-
natal depression (Field, Diego, Hernandez-Reif, Deeds, & Fi-
gueiredo, 2009; Field, Diego, Hernandez-Reif, Schanberg, &
Kuhn, 2004; Field, Hernandez-Reif, Hart et al., 1999) and pre-
mature delivery (Field, Diego, Hernandez-Reif, Schanberg, &
Kuhn, 2004; Field, Hernandez-Reif, Hart et al., 1999).
Yoga is another potential alternative therapy that, like mas-
sage, is considered safe for pregnant women. Both yoga and
massage therapy stimulate pressure receptors which leads to
increased vagal activity, so it is not surprising that they also
have similar benefits, including decreased depression (Field,
2011b). For these reasons yoga has been considered a form of
self-massage, as in the “rubbing of limbs against each other and
against the floor” (Field, 2011b). Although yoga decreases de-
pression, research has not yet demonstrated whether yoga de-
creases depression symptoms in pregnant women (Field, 2011b).
Research on yoga with non-depressed samples has suggested
a number of positive outcomes, including decreased anxiety,
pain, and premature births (Battle, Uebelacker, Howard, & Cas-
taneda, 2010; Narendran, Nagarathna, Narendran, Gunasheela,
& Nagendra, 2005). Previous studies with prenatal depression
have used yoga interventions that combined breathing, medita-
J. MITCHELL ET AL.
tion, and poses. As a result, it is not possible to determine
whether the actual poses are therapeutic, or if the changes are
related to other aspects of yoga, including meditation and
breathing exercises. The current study addressed this gap in the
literature and determined whether the actual yoga poses could
reduce prenatal depression symptoms. Specifically, our hypo-
thesis was that participation in yoga would result in decreased
depression symptoms, as measured by depressed affect and
somatic/vegetative symptom scores on the Center for Epidemi-
ological Studies-Depression scale (CES-D; Radloff, 1977). To
test this hypothesis, a yoga group was compared to an attention
Domains typically associated with depressive symptomatol-
ogy and assessed by the subscales of the CES-D include posi-
tive and depressed affect, somatic/vegetative signs, and inter-
personal distress. Research on the effects of yoga on vagal ac-
tivity suggests that decreases would occur specifically on the
depressed affect and somatic/vegetative signs subscales fol-
lowing yoga. The basis for this hypothesis was that vagal activ-
ity has increased following yoga (Sathyaprabha et al., 2008).
Since vagal activity stimulates the muscles that control facial
expressions and vocal intonation (Porges, 2001), it could be
argued that increased vagal activity in depressed pregnant wo-
men would lead to decreased depressed affect (Porges, 2001).
Vagal activity has also been linked to the regulation of so-
matic/vegetative signs including appetite and sleep, whereby
lower vagal activity was associated with eating and sleeping
problems (Bodenlos et al., 2007; El-Sheikh et al., 2007). Thus,
depressed affect and vegetative state/somatic complaints were
expected to decrease following yoga.
The sample was comprised of 24 participants from a pilot
study conducted for a larger ongoing study on yoga effects on
prenatal depression. Participants were recruited from two pre-
natal ultrasound clinics affiliated with a large private university
medical center in the South. The 24 participants were clinically
depressed pregnant women who were randomly assigned to
either the yoga treatment group (n = 12) or parenting education
attention control group (n = 12). The recruitment criteria were:
1) meeting diagnostic criteria for depression on the Structured
Clinical Interview for Depression (SCID); 2) being pregnant
with one child; 3) having an uncomplicated pregnancy with no
medical illness; 4) being younger than 40-years-old; 5) not
having a co-morbid mental health issue; and 6) not using drugs
(i.e., prescribed or illicit) that could affect cortisol levels. Previous
samples recruited from these clinics had a very low incidence
(3% - 5%) of treatment for prenatal depression (i.e., psycho-
therapy or antidepressants), so these were not exclusion criteria.
The sample comprised women ranging in age from 18- to
37-years-old, with an average age of 26.6 years. The partici-
pants were primarily low-income minorities who had a high
school education. Table 1 provides aggregate information on
the participants’ ethnicity, SES, and level of education.
The CES-D (Radloff, 1977) was administered at the begin-
ning (M = 20 weeks gestation) and at the end of the treatment
period (M = 32 weeks gestation). The CES-D is a 20-item
self-report measure that assesses frequency of current depres-
sion symptoms over the past week (Radloff, 1977). Targeted
symptoms include “depressed mood, feelings of guilt and
worthlessness, feelings of helplessness and hopelessness, loss
of energy, and disturbances of sleep and appetite” (Radloff &
Teri, 1986). Likert frequency ratings include most of the time
(6 - 7 days), occasionally, (3 - 4 days), some of the time (1 - 2
days), and rarely (less than a day). Individuals are asked to rate
each item from 0 to 3 based on how often they have felt this
way, with higher scores indicating greater frequency. Total
summary scores range from 0 to 60, with clinical levels of de-
pressive symptomatology associated with scores of 16 or higher
(Radloff, 1977). Subscale scores are provided for depressed af-
fect, positive affect, somatic/vegetative signs, and interpersonal
distress (see Table 2; Radloff & Teri, 1986). The CES-D has
acceptable validity and reliability for various demographic
Demographic characteristics of the sample.
Characteristic Frequency Percentage
Black 14 58.3
Hispanic 6 25.0
White 2 8.3
Other 2 8.4
Middle 2 8.4
Lower-Middle 5 20.8
Lower-Lower 17 70.8
Level of Education
7 - 9 Years 1 4.2
10 - 11 Years 5 20.8
High School Graduate 10 41.7
1 - 3 Years of College 8 33.3
CES-D items by subscale.
I felt that I could not shake off the blues even with the help from my
family and friends.
I felt depressed.
I felt lonely.
I had crying spells.
I felt sad.
I felt that I was just as good as other people.
I felt hopeful about the future.
I was happy.
I enjoyed life.
I was bothered by things that usually don’t bother me.
I did not feel like eating; I was not hungry.
I had trouble keeping my mind on what I was doing.
I felt that everything I did was an effort.
My sleep was restless.
I could not get going.
People were unfriendly.
I felt like people disliked me.
Note: Items 4, 8, 12, and 16 are reverse scored.
Copyright © 2012 SciRes. 783
J. MITCHELL ET AL.
variables including geographic location, level of education, age,
ethnicity (black, white, Hispanic, Asian, and European), and
language (Radloff & Teri, 1986).
The CES-D is a valid and reliable measure of depression
symptoms, and a precise tool for assessing symptom changes
across time (Weissman, Sholomskas, Pottenger, Prusoff, &
Locke, 1977). Radloff (1977) reported internal consistency
of .85 for the general population and .90 for clinical samples,
moderate test-retest reliability correlations between .51 and .67
over 8 weeks, and split-half reliabilities of .77 to .92. In a study
on black, white, and Mexican-American ethnicities, no differ-
ences were noted in internal consistency and reliability scores
among the groups (Roberts, 1980). Among low income, minor-
ity women, the CES-D had moderate criterion validity and was
related to an MDD diagnosis (Thomas, Jones, Scarinci, Mehan,
& Brantley, 2001). A similar study on low SES minorities sup-
ported the four-factor model (i.e., depressed affect, positive
affect, somatic/vegetative complaints, and interpersonal prob-
lems) originally observed in the general population (Nguyen,
Kitner-Triolo, Evans, & Zonderman, 2004).
Finally, a study on a high-risk sample of women with prena-
tal depression supported these early findings, with internal con-
sistency (Cronbach alpha) ranging from .88 to .93 (Maloni,
Park, Anthony, & Musil, 2005). Additionally, test-retest reliability
indicated stable results over time (i.e., admission, 2-weeks, and
4-weeks), as well as statistically significant (p > .01) conver-
gent validity with other depression symptoms scales (Maloni et
al., 2005). CES-D scores were also sensitive to decreases in
depression symptoms resulting from massage therapy (Field,
Diego, Hernandez-Reif, Schanberg, & Kuhn, 2004; Field, Her-
nandez-Reif, Hart et al., 1999). Together, these findings sug-
gested that the CES-D was an appropriate measure of depres-
sion symptoms for this study’s sample and design.
Women in the yoga group participated in 20-minute sessions
two times a week for a period of 12 weeks. A trained yoga in-
structor led group participants through a routine specifically
designed for women in their second and third trimesters of
pregnancy (see Table 3 for routine). The control group partici-
pated in parenting education sessions to control for the effects
of attention and social support received by the women in the
yoga group. The yoga and parenting education groups were the
same size and followed the same weekly schedule. Participants
in both groups were paid $20 for each session to compensate
for expenses related to lost wages, childcare, and transportation.
Fisher-Freeman-Halton tests revealed no significant differ-
ences between the yoga and control groups on ethnicity (x2 =
4.20, p = .26), socioeconomic status (x2 = 2.40, p = .46) or level
of education (x2 = 4.88, p = .11). In addition, a one-way
ANOVA indicated that the groups did not differ on maternal
age, F(1, 20) = .05, p = .83.
Repeated measures ANOVAs were conducted to test for
changes in CES-D scores over time for both groups. In these
analyses, “group” was designated by treatment or control con-
dition, and “time” was defined by changes from pretest to post-
test scores. Table 4 presents mean summary and subscale
scores for the CES-D by group. A significant repeated measures
- Sit cross-legged and stretch, reaching hand around back until you
can see behind you on left and then right
- Clasp hands behind you, touch face to left knee, then center, then
On hands and knees:
- Table pose—happy cat, scared cat x3
- Kneeling balance—left arm out stretched forward, right leg back,
repeat on opposite side
- Kneeling warrior
- Runner’s stretch, left knee bent and right knee kneeling, repeat on
- Stand up, legs apart, let arms hang down, hands touching floor
- Tree pose, left foot at knee or shin, repeated on right
- Dancer’s pose
- Sunset salutation x3
o Prayer position, reach hands up, hands apart, reach back in slight
back bend, then swan dive hands down to floor
o Inverted V
o Get on knees, then move feet up to hands, one by one
Stretching—seated on floor, foot to knee, reach for other foot
Sitting—hold feet in hands, making butterfly wings
Lay on side—Relaxation pose
Sit in prayer position
Mean Scores on Pretest and Posttest CES-D Summary and Subscales
by Group (Standard deviations in parentheses).
Pretest Posttest Pretest Posttest
CES-D Summary 27.50 (10.04)17.92 (8.67) 22.42 (8.83)21.42 (9.79)
Depressed Affect 8.17 (4.08)4.83 (3.59) 5.33 (3.03)5.50 (3.42)
Positive Affect 5.00 (2.59)4.08 (1.73) 5.25 (4.92)4.92 (2.68)
Somatic/Vegetative 9.50 (3.23)6.75 (2.73) 7.00 (3.81)7.58 (4.01)
Interpersonal Distress1.33 (1.23).75 (1.60) 1.43 (1.31)1.25 (1.22)
effect indicated differences between pretest and posttest CES-D
summary scores, F(1, 22) = 9.22, p < .01. Although there was
no significant group effect, F(1, 22) = 0.54, p = .82, the group
by time interaction effect was significant, F(1, 22) = 6.07, p
< .05, 2
= .22. A repeated measures by group ANOVA was
also conducted for each of the CES-D subscales. Group by time
interaction effects were significant for the depressed affect, F(1,
22) = 7.21, p < .05, 2
= .25 and somatic/vegetative subscales,
F(1, 22) = 5.98, p < .05, 2
Additional analyses with paired sample t tests were con-
ducted for the CES-D summary and subscale scores. Results
indicated that the pretest/posttest difference in CES-D summary
scores was significant for the yoga group, but not the control
group (see Table 5). Paired sample t tests for the pretest/post-
test differences in subscale scores are presented in Table 5. No
significant differences were found for the control group sub-
scale scores. Additionally, no significant differences were
found for the positive affect and interpersonal distress subscales
in the yoga group. However, the differences in pre- and post-test
scores on the depressed affect and somatic/vegetative subscales
were statistically significant for the yoga group.
Copyright © 2012 SciRes.
J. MITCHELL ET AL.
Change in pretest/posttest CES-D summary scale and subscales by group
(standard deviations in parentheses).
Scale M (SD) t M (SD) t
CES-D Summary –9.58 (11.06) –3.00* –1.00 (4.84)–.72
Depressed Affect –3.33 (3.96) –2.91* .17 (2.17) .27
Positive Affect –.92 (2.61) –1.21 –.33 (2.46)–.47
Somatic/Vegetative –2.75 (4.14) –2.30* .58 (2.27) .89
Interpersonal Distress –.58 (1.31) –1.54 –.17 (1.27)–.46
*p < .05, two-tail.
Massage therapy and yoga are thought to stimulate pressure
receptors that result in increased vagal activity and lead to de-
creased depression (Field, 2011b). Since the mechanisms of
action seem to be similar, this study hypothesized that, like
massage therapy, yoga would result in decreased prenatal de-
The results from this study offer support for yoga as another
alternative treatment for depressed pregnant women. Yoga not
only decreased prenatal depression, but also decreased de-
pressed affect and somatic/vegetative signs. These effects may
relate to the increased vagal activity previously noted following
yoga (Sathyaprabha et al., 2008). Since vagal activity stimu-
lates the muscles that control facial expressions and vocal into-
nation (affect) and has been linked to vegetative signs (Porges,
2001), it could mediate the decrease in depressed affect and
somatic/vegetative symptom scores for the yoga group. Yoga
has the benefits of moderate intensity exercise and relaxation,
while also offering improved sleep, fatigue, and stress levels
(Ross & Thomas, 2010). These results, in turn, support the
clinical utility of yoga for reducing common complaints of
pregnant women that can be exacerbated by prenatal depression.
Although the results of this study suggested a statistically
greater decrease in prenatal depression for the yoga group, this
finding may not be clinically significant. For this study, the
mean posttest CES-D summary scores for the yoga and control
groups were 17.9 and 21.4, respectively. Although the yoga
group exhibited greater symptom reduction, the mean CES-D
was still above the clinical cutoff score of 16. The yoga reduced
depressive symptoms to subclinical levels in 55% of partici-
pants compared to 11% in the control group. However, almost
half of the participants in the yoga group still reported clinical
levels of depressive symptoms.
Future research using a larger sample size will help to sup-
port these preliminary findings. In addition, studies examining
the effects of yoga and comparable treatments (e.g., massage or
exercise) will elucidate the relative efficacy of yoga in amelio-
rating prenatal depression. Additional research exploring the
mechanisms underlying yoga effects on prenatal depression
will provide further support for yoga as a viable treatment.
Nonetheless, the current study suggests that yoga poses prac-
ticed over a 12-week period during pregnancy can reduce de-
pression symptoms in depressed women.
We would like to thank all the pregnant women who partici-
pated in this study. This research was supported by an NIH
grant (HD056036), a Senior Research Scientist Award (AT001585)
and funding from Johnson and Johnson Pediatric Institute to the
Touch Research Institute. Author’s correspondence email ad-
dress is email@example.com
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