Hi there . I ' m a prenatal yoga instructor . A lot of my students have told me they found my class just by googling the cityprenatal yoga . Any good yoga instructor should be able to offer you modifications if you take a regular yoga class . Always tell your instructor that you are pregnant prior to class . Avoid deep twists . When you turn , you want to be able to bring baby with you , so use that as a guideline when practicing . if you are turning away from belly , avoid that posture . Laying on your back is actually perfectly OK provided YOU can breathe . The danger is to you , not to the baby . The fear is that your oxygen will be cut off , but if that were to happen , you would be unable to breathe and you would know it . So if you are on your back and begin to feel short of breath , roll on your side . That being said , it ' s typically very uncomfortable for women to be on their backs as pregnancy progresses so we don ' t do much on our backs in my classes and when we do , it ' s typically to stir the knees or for Happy Baby pose in which we are moving circularly or rocking side to side and not completely still .