Supporting Research: Prenatal Yoga
Overview of Research
In preparation of becoming a nonprofit organization, Prenatal International (PI) looked at 12 research articles, some of which were meta-analyses. The patterns that emerged from this group of research articles are as follows:
Most articles cited benefits of prenatal yoga for pregnant women and/or their babies (some studies also included postnatal yoga.) Primarily, the authors cited the following benefits, for both prenatal and postnatal stages as most likely to occur in healthy pregnant women:
- Decrease in hypertension
- Decrease in pregnancy related discomforts such as back pain, pelvic pain, headaches, and nausea
- Decreased in stress levels
- Increase in pleasure
- Fewer complications in delivery process
- Decrease risk of preterm labor
- Many of the authors cited the following benefits as most likely to occur in depressed or high-risk pregnant women:
- Decreased in stress levels
- Decrease in anxiety
- Decrease cortisol and other stress hormones and increase immunity
- Decrease the length of labor
- Decrease the need for labor induction
- Decrease in leg and back pain
- Decrease in hypertension
- Decrease the need for cesarean birth
- Decrease in gestational diabetes
- Decrease in intrauterine growth restrictions
- Marked decreases in rates of mortality for both babies and (mothers) when yoga programs are introduced, particularly in third world countries
Many studies cited the caveat that not all yoga poses were designated for working with pregnant woman, but prenatal yoga programs make modifications accommodations in types of poses and their duration. Many studies also alluded to the role of breathing and meditating for all women alongside yoga techniques. There was general agreement among experts that there was “no evidence of adverse events” stemming from yoga classes, leading investigators to conclude that prenatal yoga classes were safe for people during pregnancy
Many other studies advised that although the existing body of knowledge is helpful and well-documented, there is still a need for more “randomized control trials…to further examine the content of effective interventions, intervention means and fluency…”
Effects of prenatal yoga
A systematic review of randomized controlled trials
A Japanese study, Effects of prenatal yoga: a systematic review of randomized controlled trials (RCTs), published in 2015, out of 54 citations reviewed 8 studies that met the criteria for RCTs. (Yasuyuki Kawanishi, et al)
Their findings suggested that not only did prenatal yoga help reduce pelvic pain and hypertension, it had a positive effect on people’s mental condition such as, depression, stress levels, and anxiety levels. One of the studies they review reported that in high-risk patients with preconditions the practice led to “significantly fewer cases of pregnancy-induced hypertension, gestational diabetes, and intrauterine growth restrictions.”
The studies included findings of prenatal yoga’s effect on other related events around birthing such as, an easier delivery with fewer obstetrical complications and the length of delivery.
The authors cautioned that further RCTs are needed to add to this body of knowledge.
Yoga in pregnancy
Many poses are safer than once thought
Also in 2015, Harvard Medical School generated another article entitled, Yoga in pregnancy: Many poses are safer than once thought, (Marilyn Wei, MD, JD) Many professionals theorized that that the yoga poses could do harm during pregnancy. In this article the author negates this theory, but issues some caveats in teaching yoga poses. They propose that some poses like Happy Baby pose and Corpse pose be avoided, but other poses could be modified using chairs, a wall, or blocks (Half Moon, Warrior III, and Tree). During this study, the vital signs of participants and their babies were monitored during the yoga sessions, and the vital signs were “normal during the poses and after the sessions.”
A systematic review
The effects of yoga on pregnancy & The effects of yoga in prevention of pregnancy complications in high-risk pregnancies: A randomized controlled trial
Corroborating previous studies, a meta-analysis done in 2020, and was reported in the European Journal of Obstetrics & Gynecology and Reproductive Biology by Rachel Kwon, et al. These authors looked at 175 studies, five of which met the criteria for inclusion, particularly the fact they were RCTs (randomized controlled trials). The major findings showed that antenatal (prenatal) yoga appeared to have positive effects on dealing with patient anxiety during pregnancy depression, stress levels, pain responses, and “emotional-wellbeing.” Further, they suggest that prenatal yoga also decreases cortisol levels. This is important since these factors “can cause adverse pregnancy outcomes and changes in fetal development.”
American Pregnancy Association
Based on its own internal research, he American Pregnancy Organization (AMO) promulgates a list of benefits of prenatal yoga, several of which echo the findings of most other research. However, they tout the benefits of having a strong support system during pregnancy, including the yoga class that allows participants to share their experiences with each other.
The other benefits that are on the list are as follows:
- Development of proper breathing and relaxation techniques for easier labor
- Reduction of stress
- Increase in endurance, flexibility and strength
- Reduction in lower back pain
- Reduction in nausea
- Reduction in carpal tunnel syndrome
- Reduction in headaches
- Decrease in the risk of preterm labor
- Decrease in the risk of intrauterine growth restriction
- Decrease in hypertension
- Improved fetal outcomes
Prenatal yoga for young women
A mixed methods study of acceptability and benefits
A study done on November of 2019 from BMC by Amanda Styles, et al., stated that young women (below age 24) in particular, showed high rates of “psychological -distress, social complexity and trauma” during pregnancy. The patients sought to have feelings of well-being, but were often excluded from activities such as yoga. (As a group, they were largely ignored in experimental studies.)
The study examined the acceptability of the benefits of yoga for patients under 24. Participants were given twice weekly yoga sessions for the duration of their pregnancies. Baseline statistics were gathered before and after the duration, and surveys were done before and after the sessions. 60% of the participants “had a history of documented psychological distress.” The 26 participants in the study had a positive attitude going into the study, but only 15 could attend the sessions. The obstacles to the study’s participant attendance was “practical, not attitudinal.” Their health and transportation were not under their control.
However, participants who persevered saw solid benefits:
- Preparation for labor
- Decrease in psychological stress
- Social connection with classmates
- Stronger bonds with their unborn babies
- Better relaxation
Prenatal Yoga for Mental Health
A Systematic Literature Review
This meta-analysis from Indonesia was written in 2019, by Renita Rizkaya Danti, et al. Included in the literature review were 12 studies out of a total of 942 that they considered. They stated that maintaining a “healthy mental condition during pregnancy,” and prenatal yoga contributed to that condition. One difficulty they cited was that there was “less parental knowledge and family support for yoga because it was little known. They concluded that yoga is both safe and beneficial for both pregnant women and their babies. Among the benefits they cited:
- Improving nerve response to …reduce cortisol levels
- Mood improvement
- Promoted positive thinking
- Reduced anxiety
- Stress and depression
- Increased confidence during pregnancy and delivery
Yoga for pregnant women with symptoms of depression and anxiety
A randomized controlled trial
This study done in 2015, by Kyle Davis, et al., was a randomized controlled trial (RCT) that focused on depression and anxiety in pregnancy. The authors acknowledged the benefits from yoga that pregnant women preferred over “nonpharmacological treatments.” The RCT control group consisted of treatment-as-usual (TAU). Both treatments produced acceptable outcomes, reducing symptoms of depression and anxiety, but only yoga “significantly outperformed TAU on reduction of negative affect.”
There are benefits to prenatal yoga
but lingering questions remain
In 2018, a freelance writer/editor writing in the journal ScienceNews reported on a few studies that showed a comparison of those participants who had taken prenatal yoga during pregnancy, and found among those who included yoga in their routine lessened back pain especially in the lower back, lower levels of cortisol due to stress, and higher levels of immunoglobulin A that indicates immune function. She cites a 2015 study that pregnant women who had depression who took yoga classes “experienced significant decrease in depression levels only when their practice included breath work, meditation or deep relaxation” in addition to their usual practice.
Systematic Review of Yoga for Pregnant Women
Current Status and Future Directions
A meta-analysis in 2012, was done by Canadian researchers, Kathryn Curtis, et al. They isolated five studies out of 689 that contained randomized control trials. A very large body of literature that were not RCTs compiled by the authors were missing the rigor of RCTs. The research they used in the five studies did allow the authors to come to some overall conclusions: Improvement in psychological domains during trials Reduction in discomfort and pain “during pregnancy and labour” Decrease in birth weight and number of preterm births Positive evidence that yoga is well-suited to pregnancy
American College of Obstetricians and Gynecologists (ACOG)
Similar to the AMO, the American College of Obstetricians and Gynecologists (ACOG) based their list of safety and benefits of exercise to their pregnant patients.
ACOG listed benefits for both the person pregnant and the baby:
- Reduction of back pain
- Lessens constipation issues
- Could reduce risks of cesarean birth, gestational diabetes, preeclampsia
- Assists healthy weight gain
- Fosters overall fitness and increases strength of heart vessels
- Assists weight loss after giving birth
ACOG also cites the changes in the patient’s body that have an impact on the body:
- Promotes joint mobility and decrease in the risk of injury
- Stability and balance
- Increased need for oxygen
Among the approved exercises that ACOG suggests is yoga and pilates because they are designed and modified to “accommodate a pregnant woman’s shifting balance.”
They also provide guidelines for exercises that people should avoid and the warning signs to stop exercising.
The effect of integrated yoga on pregnancy outcome in hypertensive disorder of pregnancy
A randomized control trial study
Researchers at the Lady Hardinge Medical College for women are based in New Delhi, India. The study was done in 2021, and the authors were Amirita Makhija, et al. They cited one major
Practicing yoga for 40 minutes three times a week for four weeks showed that yoga “effectively reduced systolic and diastolic blood pressure in mild hypertensive disorder in pregnancy.”
The second finding showed one that many other researchers had reported in numerous other RCTs, that yoga increased the maternal comfort during labor and shortened the time in labor.
Maternal Lifetime Trauma Exposure, Prenatal Cortisol, and Infant Negative Affectivity
By Michelle Bosquet Enlow, et al. (paper presented online)
At the time of this meta-analysis, 2017, only a sparse number of studies in the field dealt with “the impact of maternal lifetime trauma exposure on infant temperament.” This analysis looked at the extant research through 2017. The analyses included measures such as the Life Stressor Checklist Revised LSC-R), Infant Behavior Questionnaire, Revised (IBQ-R), and the Crisis in Family Systems, Revised (CRISYS-R). This data were taken from 29 studies with 2217 pregnant women. One additional quantitative measure was the role pregnancy yoga in reducing stress and depression that showed a high level of validity. That measure also showed that the intervention reduced the tolerance for pain, higher odds for reduced time in labor, and a better chance of a normal vaginal birth.
Associations with maternal trauma history and infant distress and the following:
- Infant sadness, but not fear
- “Maternal psychobiological functioning and caregiving behaviors, like dissociation and withdrawal, foster the possibility of infant sadness
- A history of maternal trauma also is connected to either hyper- or hypo- “arousal …among infants exposed to higher cortisol levels”
- Research also suggests that this trauma may also be linked to the risk of “engaging in insensitive caregiving behaviors” that “may compromise the infant’s developing stress regulatory abilities”
- Research also showed long-term effects of exposure to maternal trauma and child emotional and behavioral problems
Supporting Research: Doula
The Effects of Doula Care on Birth Outcomes and Patient Satisfaction in the United States.
The Eleanor Mann School of Nursing Undergraduate Honors Theses Retrieved from Lynae Carlson (2021)
Meta Analysis (confined to US populations of adolescents, women in poverty, intellectual disabilities)
Studies showed an array of benefits:
- Lower rates of Cesarean births
- Fewer premature babies
- Fewer Epidurals
- Decreased in time in labor
- High 5-minute Apgar scores
- More patients breast feeding
- Cost saving (one study saw a 73.3% saving)
- “Gave women a voice”
- Provided confidence
- Relieved stress
- Participants in many studies said they were more satisfied when they had “cultural similarities with the doulas”
- Provided women with reliable information
Recommendations from findings:
- Need for a “more culturally and ethnically diverse doula workforce”
- Need for “increased doula raining in communication and relationship building”
- Need for more studies in different countries round the world
- It would be helpful to have “standardized surveys evaluating patient satisfaction of doulas using a numerical scale would also provide more direct comparison between the subpopulations and help guide the doulas in providing better care”
- “Doula care could be a cost-conscious and patient-centered method to address the United States’ high infant mortality rate in comparison to European countries”
Note”: we could extrapolate these recommendations to the international communities.
Doulas and Their Potential Impact on the Maternal Health Crisis
Michela Crowley, March, 2021, New York City
“Participants who had a doula present throughout their birth showed:
- 39% decrease in the risk of Cesarean
- 15% increase in the likelihood of a spontaneous birth
- 10% decrease in the use of any medications for pain relief
- Shorter labors by 41 minutes on average
- 38% decrease in the baby’s risk of a low five-minute Apgar score
- 31% decrease in the risk of being dissatisfied with the birth experience”
Disparities within the Maternal Death Crisis:
- Black women in the US “are almost 4 times as likely to die from childbirth related complications than white women”
- The rate for women in NYC is 12x as likely
- This study shows that these statistics “can be directly linked to factors such as:
- Poverty
- Chronic stress/intergenerational trauma
- Lack of access to health care
- Medical racism
In order to protect Black mothers and their babies:
- They are safer “when cared for by Black providers”
- Provide funds to support organizations that provide/train doulas
- Refer services of Black workers
Impact of Doulas on Healthy Birth Outcomes
Kenneth J Gruber, et al – The Journal of Prenatal Education 22(1), pp. 49-58
This is a study comparing “two groups of socially disadvantaged mothers at risk for adverse outcomes”:
- One group received prebirth help from a doula who was certified
- Doulas provide emotional, informational, and physical support
- Lower incidences of Cesarean births
- Lower occurrences of low birth weights
- Fewer birth complications, medical interventions
- More likely to initiate breast feeding
- Emboldens women to “take charge of their own prenatal health, thus improving birth outcomes.”
- The second group of mothers who chose not to participate with a doula
- Higher incidences of Cesarean births
- Four times more likely to have lower birth weights
- Less likely to initiate breast feeding
- More birth complications and more medical interventions
- “A skilled doula empowers a woman to communicate her needs and perceptions and actualize her dream of a healthy, positive birth experience.” (p/49)
- “This study indicates that both of these groups can build their self-efficacy and together (with the doulas) as partners in this journey, improve birth outcomes.” (p.57)
- “Questions to be examined include individual compared to group care with doula assistance, …the role of informed decision making in birth outcomes, and perceptions and decision-making process of women in opting for the support of a doula.” (p.57)
Community-Based Doulas and Midwives on Addressing the U.S Maternal Health Crisis
By Hardy, et al April 14,2020
This report focuses on disparities in health care for Black and Hispanic birthing people as well as LGBTQ birthing people. The authors state that “Black and indigenous people are three to four times more likely to die from pregnancy-related causes than non-Hispanic white women.” This has an effect on 50,000 women per year. The report further states that the “driving force of disparities in maternal mortality” is racism.
Since the disparities exist in underserved communities, the solutions as the authors see it is to: Provide greater access to doulas and midwives while also supporting the medical system.
The report also contains a wide variety of interviews with people affiliated with different professional groups that work with birthing people. The interviewees shared both information and perspectives on this crisis. The following is a brief synopsis of the results of these interviews that fall into three categories:
- “The reentering of community and humanity in pregnancy-related care.”
- Stop the exploitation and discrimination done to the “vulnerable members of societies
- Build relationships and restore trust in those communities.
- Create a whole person approach to medical care.
- Develop guidelines to “integrate doulas and midwives into the system and define the role of government.
- Focus on racism and bias in providing education and renew respect for these caregivers.
- Change the focus of birthing as strictly a medical procedure.
- Support community-based care providers that include workers of color; value birthing people’s traditions; and “preserve the autonomy of midwives and doulas.”
- Redo policies to reflect “a progressive vision” for maternal care.
- Offer birth options to birthing people.
- Value the “autonomy and self-determination “of both birthers and workers.
In addition, the report contains a great variety of information and perspectives from the professionals interviewed. The remarks are categorized as follows:
- Recentering of community and humanity in birthing care
- Interrupting harm
- Building power and trust
- Centering the whole person
- Integrating the birthing professionals into the health care system and the role of the government
- Licensure and scope of practice
- Reimbursement
- Policy recommendations
- Keeping the vision in mind
- Fund existing community-based organizations
- Expand access to training and education
- Improve integration into the medical system
- Provide access and the autonomy to choose a range of birth options
There is also an extensive list of references.
Maternal Mortality Rates
The World Health Organization (WHO) defines maternal mortality as “the death of a woman while pregnant or within 42 days of termination of pregnancy, irrespective of the duration and the site of the pregnancy, from any cause related to or aggravated by the pregnancy or its management, but not from accidental or incidental causes.”
Maternity Mortality Rates in the United States
According to the World Health Organization the US ranks 55th in the world for maternal mortality, the worst in all developed countries. As a country the United states has a maternal mortality rate of 23.8 (deaths per 100,000 live births). When looking only at non hispanic white maternal mortality the rate is 19.1 compared to black maternal mortality which is currently 55.3.
When we take a closer look there are big discrepancies between states with California having the lowest maternal mortality rates (4.0) and Louisiana having the highest (58.1). The states with the highest maternal mortality rates are:
- Louisiana – 58.1 per 100k
- Georgia – 48.4 per 100k
- Indiana – 43.6 per 100k
- New Jersey – 38.1 per 100k
- Arkansas – 37.5 per 100k
- Alabama – 36.4 per 100k
- Missouri – 34.6 per 100k
- Texas – 34.5 per 100k
- South Carolina – 27.9 per 100k
- Arizona – 27.3 per 100k
More states that are above the national average are: Tennessee, Wyoming, South Dakota, Idaho, Kentucky, Florida and Rhode Island.
Some of the main reasons that rates are so high in the US are: Obesity, high blood pressure, racism, and high cesarean rates. Many of these things can be helped by implementing prenatal yoga, doula services as well as improving health care.
Maternity Mortality Rates in the United States, 2020
(CDC) Donna L Hoyert, Ph.D. Division of Vital Statistics
The World Health Organization defines a maternal death as “the death of a woman while pregnant or within 42 days of termination of pregnancy, irrespective of the duration and the site of the pregnancy, from any cause related to or aggravated by the pregnancy or its management, but not from accidental or incidental causes.”
WHO characterizes the maternal mortality rate as the number of cases per 100,000 deaths per live births. In 2019, the overall rate was 20.1 compared to 23.8 deaths in 2020. While maternal death rates for white, non-Hispanic women stayed relatively stable over the last few years, there was a significant increase in maternal death rates for non-Hispanic Black women (19.1 for non-Hispanic white women compared to 55.3 deaths among Blacks).
In addition to race, rates also drastically increased for women over 40 (the age group under 25 had 13.8 deaths per 100,000 to 107.9 for the 40 and older women of all races.) The results were statistically significant.
Statistically, the maternal death rates fluctuate depending on the reporting using death certificates.
Global causes of maternal death
A WHO systemic analysis (a meta-analysis)
Lale Say et al – Chart p.325
This analysis extrapolated 23 studies that encompassed data from the years 2003 through 2012. It identified four main causes of maternal deaths worldwide:
hemorrhage, hypertensive disorders, sepsis, and embolism resulted in more than half of all cases. The study also included abortions among the direct causes. A quarter of all deaths resulted from indirect causes. Datasets (417) were taken from 115 countries and were reported by regions around the world.
The data showed some marked disparities among regions, and the greatest disparities occurred
between developing regions and developed regions. Data shows that Sub-Sharan Africa deaths far outnumbered the results in Northern Africa, Eastern Asia, Western Asia, and developed regions. For example, the percentage of maternal deaths from the main causes are as follows:
The documentation also included data about complications of delivery, obstructed labor and indirect causes involving HIV-related deaths, pre-existing conditions among others.
The authors some issues /concerns policy and practice:
- Some data from certain parts of the world are not available and “estimates were obtained on the basis of modeling” and India and Nigeria “together accounted for a third of global maternal deaths.”
- Sometimes the date is incomplete or missing. A case in point is abortion-related deaths that seem to be under reported.
Maternal Mortality in Uganda
“In March 2021, the Uganda Bureau of Statistics reported that the maternal mortality rate dropped from 438 deaths per 100,000 (live births) in 2011 to 368 deaths per 100,000 in 2021.”
Although there has been a continual decrease in the number of deaths in the past 20 years, Uganda is still “far above the global average” of 152 deaths per 100,000
The report relates that the causes of deaths, are preventable, but there are three reasons for the deaths are still high:
- First, there are cultural norms that play a part in seeking care. The decision making is sometimes not up to the women, but the family may decide that the women do not need care in a timely manner. Therefore, complications can lead to “serious consequences.”
- Second, the issue of distance from the facility, and the conditions on the roads may pose problems for the pregnant women.
- Third, there are delays getting care once they arrive at the facility, because the conditions and equipment may not be adequate. In addition, there may not be sufficient staffing on hand to handle emergencies.
In 2020, the World health Organization (WHO) and the Republic of Korea pledged $10 million to “improve health services across Uganda, including maternal health.” These funds are directed at:
- Obtaining ambulances
- Training staff
- Improving health facilities
Funds may help but will not be “sufficient to end maternal mortality in Uganda.”