General Yoga Benefits
Yoga is a beneficial complementary therapy for many medical conditions. Many common discomforts of pregnancy cause symptoms that are similar to those that surface in other medical conditions. Because yoga is used for symptom management in these disease states, it is not unreasonable to infer that yoga's benefits may also carry over to help with similar discomforts of pregnancy.

The health of a wide range of people may be improved with regular yoga practice. The practice of hatha (gentle) yoga can increase strength, endurance, flexibility and overall physical fitness.¹⁶ Patients with hypertension may benefit from yoga therapies; researchers have documented statistically significant decreases in systolic and diastolic blood pressures and mean arterial pressures, suggesting that yogic practices may have long-term benefits on health.^10,11

Cardiac patients who practice yoga experience an overall enhanced sense of well-being, decreased anger tendencies and an improved sense of meaning in life.¹⁷ In an often-cited report, patients with asthma were randomized to receive yoga training or continue with regular medication use. The researchers documented significant improvements in the yoga group, which had fewer and less severe asthma attacks.¹⁸ Finally, multiple randomized, controlled trials recently demonstrated that yoga may be effective in significantly reducing chronic back pain.^19,20

Forms of Yoga
Numerous types of yoga programs and classes are available, including prenatal yoga, hatha yoga, iyengar yoga, Bikram yoga, ashtanga yoga and others. Although yoga is a type of exercise, it is not typical of all exercise. For example, yoga involves more than mere physical posture changes and the exertion that are integral to typical American ideas of exercise.

Three yoga tools are commonly used: asanas (poses), pranayama (control of breath) and meditation. Each principle is essential to all yoga, but some types of yoga emphasize certain tools more than others. One goal of yoga, especially prenatal yoga, is to focus on body awareness. This involves a concentration on uniting the breath and the body through movement and balance in poses. Asanas can be modified in intensity and position to best fit the person performing them.

Prenatal yoga is a gentle form of hatha yoga, in which instructors are aware of the various needs of the pregnant woman and are able to adapt poses to fit these needs.

Not all types of yoga are appropriate for pregnancy. For example, ashtanga yoga and power yoga involve difficult poses and tend to be more strenuous, and Bikram yoga takes place in rooms set to an ambient temperature of up to 100 degrees Fahrenheit. Unless the woman is an experienced yoga practitioner, these forms of yoga are typically not recommended during pregnancy.

Additionally, certain poses are discouraged at various times during pregnancy; a qualified prenatal instructor can guide a patient through safe practices. Finally, strenuous exercise should be avoided if a pregnant woman has a history of miscarriages, a herniated disc or other back injury, or cervical insufficiency.⁹ NPs must ensure that patients who wish to pursue a yoga exercise routine are aware of these caveats.

Guidance for NPs
Table 1 provides an assessment tool to determine a patient's ability to use yoga for relaxation, mindfulness and exercise. The assessment findings assist in determining whether to recommend or discourage the practice of prenatal yoga and provide for the tailoring of recommendations to meet the needs of the individual woman.

The pregnant woman who is deemed eligible for yoga practice requires education about the types of yoga and the possible benefits (Table 2). Table 3 provides safety information to be shared with patients who decide to pursue yoga during pregnancy.

Expected outcomes of prenatal yoga practice are increased relaxation, increased sense of well-being and decreased symptoms related to common discomforts of pregnancy. Continually assess each patient's eligibility for ongoing yoga participation, and monitor maternal-fetal health as part of routine obstetric care.

Putting It Into Practice
Published guidelines for prenatal yoga are somewhat limited by an insufficient quantity and quality of research. The ethical implications of controlled experimentation on pregnant women prevent tightly controlled studies. Therefore, evidence-based articles on the nonpregnant population and research about exercise during pregnancy form the foundation of the recommendations contained in this article.

Little research has been done on populations other than healthy pregnant women, so whether pregnant women with complications may benefit from yoga or another form of exercise is unclear. The recommendations contained in this article should be updated as research becomes available, and as feedback is received from health care providers, patients and yoga instructors.

Patricia Kinser is a women's health nurse practitioner who is a member of the faculty at Bon Secours Memorial School of Nursing in Richmond, Va. She is a certified prenatal yoga instructor at 4025 Yoga & Wellness in Richmond. Reach her at prenatalyogarichmond@yahoo.com. Carrie Williams is a women's health nurse practitioner in Charlottesville, Va.

First published May 2008.