Systematic review of the role of yoga in improving pregnancy outcomes

There are 4.3 births every second in the world signifying the magnitude and importance of pregnancy.  The purpose of this study was to review yoga interventions implemented from 2008 to 2013 and examine whether yoga can be an efficacious approach for positively influencing maternal and birth outcomes in pregnancy.  A systematic search was conducted for quantitative articles in pregnancy involving all schools of yoga.  Following were the inclusion criteria for a study to be included: (1) published in the English language; (2) from the following databases: Medline, CINAHL (Cumulative Index to Nursing and Allied Health), or Alt HealthWatch; (3) between the years January 2008 and December 2013; (4) include any form or school of yoga as an intervention; (5) use any quantitative study design for evaluation; and (6) implemented in prenatal or postnatal period of pregnancy. A total of 13 articles met the inclusion criteria of which five were from the United States, four from India, two from Taiwan and one each from Korea and Thailand. Twelve were from prenatal studies and one was from a postnatal study.  Of the twelve prenatal studies eight showed positive changes in maternal psychological or birth outcomes. Of the eight studies that showed positive results, five used randomized controlled designs. The duration of yoga interventions varied from 4 hours to 48 hours, and the mean was 17.1 hours (s.d. 12.9).  Limitations of the studies have been discussed.  Yoga appears to be a promising intervention for pregnancy.