1. Systematic review of the role of yoga in improving pregnancy outcomes
Manoj Sharma, MBBS, MCHES, Ph.D., FAAHB
Paul W. Branscum, Ph.D., RD
Session 3200, American Public Health Association’s 142nd Annual Meeting
Monday, November 17, 2014; 12:30 PM - 1:30 PM

2. Introduction
The birth rate of the world is estimated as 18.9 births/1,000 population which translates to about 255 births per minute or 4.3 births every second
Prenatal care, natal care and post natal care are salient pillars for public health programming
However prenatal care is often not associated with improved birth outcomes
Emotional stress and anxiety during the prenatal period have been associated with premature births, low birth weight and adverse fetal neurodevelopment and child outcomes

3. Common Complications of Pregnancy
Pregnancy induced hypertension
Preeclampsia
Eclampsia
Gestational diabetes mellitus
Premature rupture of amniotic fluid
Small fetus for gestational age
Large fetus for gestational age
Intrauterine growth retardation
Low APGAR score at birth
In order to make pregnancy event free and improve birth outcomes yoga has been suggested as an alternative and complementary system of medicine to be practiced both during prenatal and post natal periods

4. Yoga & Characteristics of Yoga Users
Yoga is an ancient practice originating in India over 4,000 years ago
Yoga has been demonstrated to reduce stress and induce relaxation
2002 National Health Interview Survey (NHIS) found about 5.1% of US population or over 14 million people were yoga users
85% Caucasians
76% females
Mean age of 39.5 years
A majority of yoga users (61%) felt yoga was important in maintaining health

5. Stages of Ashtangayoga
Yama: Techniques for successful living in society
Niyama: Techniques for managing and purifying self
Asaana: Postures for physical homeostasis & mental balance
Pranayama: Breathing techniques for physical homeostasis & mental balance
Pratihara: Techniques for developing dispassion toward senses for mental balance and equanimity
Dharana: Concentration techniques for mental balance and equanimity
Dhyana: Meditation techniques for mental balance and equanimity
Samadhi: Universal consciousness

6. Previous study
A literature review was published in 2008 that examined published studies on the effectiveness of mind-body interventions conducted during pregnancy on perceived stress, mood, and perinatal outcomes.
The study summarized the results from 12 such trials and found that sample sizes were small and not all studies used control groups.
The results showed there was modest evidence for the efficacy of mind-body interventions during pregnancy in the form of higher birth weight, shorter length of labor, fewer instrument-assisted births, and reduced perceived stress and anxiety.

7. Research Questions
Has yoga been found to be efficacious in improving experience and birth outcomes of pregnancy since the 2008 review?
Is there sufficient data available to draw conclusions regarding the efficacy of yoga in pregnancy?
What are the methodological limitations of present research studies and how can these be addressed in future research?
What are the common outcome measures measured by studies and which ones are more important for future studies?

8. Methods
The method used in this study was a systematic qualitative review of interventions obtained from following databases:
CINAHL (Cumulative Index to Nursing & Allied Health)
MEDLINE
Alt HealthWatch

9. Inclusion & exclusion criteria for studies
Inclusion criteria:
(1) be published in the English language;
(2) included in following databases: Medline, CINAHL (Cumulative Index to Nursing and Allied Health), or Alt HealthWatch
(3) between the years January 2008 and July 2013
(4) include any form or school of yoga as an intervention
(5) use any quantitative study design for evaluation
(6) implemented in prenatal or postnatal period of pregnancy
Exclusion criteria:
(1) studies that did not evaluate the intervention or implemented a qualitative design
(2) studies done in 2007 or before;
(3) articles published in languages other than English
(4) did not index in 3 selected databases

10. CINAHL, Medline, Alt HealthWatch
Phase I: Boolean Logic
CINAHL, Medline, Alt HealthWatch
Terms: Yoga AND Pregnancy; Yoga AND Pregnancy Outcome; Yoga AND pregnant; Yoga AND Pregnant women
Articles Before 2007 Excluded
Medline n= 42
Alt Watch n=64
CINAHL n= 54
Total articles remaining = 323
Total Articles Returned:
Medline n= 67; 19; 26; 30 = 142
Alt HealthWatch n=74; 7; 45; 50 = 176
CINAHL n=113; 4; 24; 24 = 165
Total = 483
Duplicate Articles
(n=179)
Other language ( n=3)
Review/Discussion/Other Articles
(n=126)
Phase II: Distillation
Total Articles Excluded (n=308)
Total Articles Remaining (n=15)
Not quantitative (n=2)
Phase III: Manuscript and Reference Review
Total Articles Excluded: (n=2)
Total Articles Included: (n=13)
Articles satisfying inclusion criteria, distillation, and review
(n=13)

11. Summary of Results…1 A total of 13 studies met the inclusion criteria
12 were in the prenatal period and 1 was in the post natal period.
Of the 13 interventions five were done in the United States, four in India, two in Taiwan and one each in Korea and Thailand.
Of the 13 interventions seven used randomized controlled designs, one used quasi experimental design, four used pretest posttest designs, and one was an observational nested case control design
The mean sample size calculated for all 13 studies in this review was with a standard deviation of and range of 15 to 138

12. Summary of Results…2
The sites of the yoga intervention for arthritis were primarily in hospitals (n=8), followed by outpatient clinics (n=2), and community settings (n=2), and for one study the site could not be determined.
The school of yoga was not identified by four studies. It was identified as Mindfulness based Iyengar yoga by two studies, Integrated yoga by three studies, Hatha yoga by one study, Sophrology by one study, combination of yoga and Tai chi by one study and combination of yoga and Pilates by one study
The duration of yoga interventions varied from 4 hours to 48 hours. The mean was 17.1 hours (s.d. 12.9).

13. Outcome Measures Used Mental Health: Related to Birth outcomes:
Stress
Anxiety
Depression
Related to Birth outcomes:
Length of labor
Birth weight of newborn
Apgar score
Less commonly used measures:
Assessment of complications
Sleep assessment
Quality of life
Platelet count
Serum uric acid

14. Authors, year Design & sample size
Interventions…1
Authors, year Design & sample size
Age
Intervention
modality
Intervention dosage
Salient findings
Chuntharapat et al. 2008
Randomized controlled trial: (n=37 x 2)
18-35 years
Asanas, Om chanting,
breathing exercises, yoga nidra (relaxation), dhyana (meditation)
Six, 60-min yoga sessions [6 hours]
-- Maternal comfort was higher for yoga group
-- Labor pain was less in yoga group
-- Duration of first stage of labor and total duration of labor was shorter in yoga group
Kim et al.
2008
Nested case-control design: (n=69 x 2)
Exp.: 29.6 ± 0.3; Cont.: 28.8 ± 0.4
Sophrology or dynamic relaxation based on yoga
2 hours per week for 4 weeks
[8 hours]
-- No difference (p > 0.05) in the no. of neonates born with meconium-stained amniotic fluid or the number of babies with Apgar score ≤ 7 at 1 and 5 minutes

15. Authors, year Design & sample size
Interventions…2
Authors, year Design & sample size
Age
Intervention
modality
Intervention dosage
Salient findings
Beddoe et al.
2009
Pretest posttest design (n=16)
Mean age 30.4 years
Mindfulness-based yoga intervention of Iyengar yoga
7 weeks; 75 minute each session
[9 hours]
-- Significant decrease in perceived stress (p <.05) from pretest to posttest
-- There was no change in state anxiety
Satyapriya et al.
Randomized controlled trial (n=45 x 2)
Yoga 26.23±2.98 Cont.
25.47±2.87 years
Integrated Approach to Yoga
16 weeks, 60 min each session
[16 hours]
-- In the yoga group perceived stress decreased by 31.57% as opposed to an increase by 6.60% in the control group
(p=0.001).

16. Authors, year Design & sample size
Interventions…3
Authors, year Design & sample size
Age
Intervention
modality
Intervention dosage
Salient findings
Beddoe et al.
2010
Pretest posttest design (n=15)
Age range years
Mindfulness-based yoga intervention with Iyengar yoga
7 weeks; 2 hour each session per week
[14 hours]
-- Women who took the intervention in the second trimester had significantly fewer awakenings and less perceived sleep disturbance at posttest than at pretest.
-- No effect for women in the third trimester
Rakhshani et al.
Randomized controlled trial (n=51 x 2)
Yoga ± 2.98 Cont ± 2.87 years
Integrated Approach to Yoga
1-hour three
times a week from 20th to 36th week of gestation (16 weeks)
[48 hours]
-- Yoga group performed better in Physical (effect size = 0.48), Psychological (effect size = 0.65), Social Relationships (effect size = 0.65), and the General
Health (effect
size = 0.65) domains

17. Authors, year, Design & sample size
Interventions…4
Authors, year, Design & sample size
Age
Intervention
modality
Intervention dosage
Salient findings
Sun et al.
2010
Quasi experimental design (n= 45, 43)
Yoga 28.2± 3.1 Cont
28.5± 3.9
Asanas, relaxation, and meditation
Videotape + practice at home x weeks
[18-21 hrs.]
-- Yoga group had fewer pregnancy discomforts than control group (38.28 vs ) at weeks of gestation
Field et al.
2012
RCT (n=28 x 3)
Mean 26.6 years
Yogic asanas
20 min twice weekly x 12 weeks
[8 hours]
-- For yoga group depression scores decreased (F= 82.40, p<.001); anxiety scores decreased (F= 26.23, p< .001) as compared to control.
Muzik et al.
Pretest posttest (n= 18)
Mean age (4.98) years
Mindfulness yoga
90 min session per week for 10 weeks
[15 hours]
-- Symptoms of depression were significantly reduced (p < 0.025)

18. Authors, year, Design & sample size
Interventions…5
Authors, year, Design & sample size
Age
Intervention
modality
Intervention dosage
Salient findings
Rakhshani et al.
2012
RCT
(n= 30, 38)
Mean age about 27 years
Breathing exercises, postures, and meditation
1-hour session x thrice a week [28 hours]
-- Yoga group had significantly fewer cases of Intrauterine Growth Retardation (p=0.05) and preterm deliveries (p=0.04)
-- Yoga group had fewer cases of pregnancy induced hypertension (p=0.02) and preeclampsia (p=0.04)
Field et al.
2013
(n =46 x 2)
Mean age 26.6 (±5.5) years
Tai chi and yoga combined
20 min
session per week for a period of 12 weeks
[4 hours]
-- Tai chi/yoga group had lower
depression scores (p<0.001)
-- Tai chi/yoga group had lower negative affect (p < 0.001) and somatic/ vegetative symptoms
scores (p <0.01)

19. Authors, year Design & sample size
Interventions…6
Authors, year Design & sample size
Age
Intervention
modality
Intervention dosage
Salient findings
Jayashree et al.
2013
RCT
(n=30, 38)
Yoga 27.7 ± 5.1 Cont ± 5.2
Integrated meditative yoga
1 hour session three days / week for 12 weeks
[36 hours]
-- In the yoga group there were 3 (10.3%) cases of pregnancy induced hypertension/ preeclampsia while there were 12 (37.7%) cases in the control group (p = 0.018)
Ko et al.
Post natal
Pretest posttest design (n=23)
Mean age ± 4.18 years
Yoga and Pilates
Exercise Program
Once a week 60 min. session
for 12 weeks by a professional coach
[12 hours]
-- Statistically significant reductions in the participants’ body weight, body fat percentage,
fat mass and basic metabolic rate were observed (p < 0.001)

20. Discussion & Conclusions
From the 12 prenatal studies a majority (n=8) demonstrated positive changes in maternal psychological or birth outcome measures related to pregnancy. Three studies had mixed results where some of the indicators showed improvement while other measures did not change. One study that used nested case control design showed no change.
The review looked at 13 studies (12 prenatal studies) of which seven used randomized controlled designs.
The sample sizes have generally been small with only two studies having sample size over 100
Wide variability of intervention dosage that has ranged from 4 hours to 48 hours with a mean of 17.1 hours