However, there is an "easy'" option that will not only help relieve heartburn, but also aid in your other prenatal yoga goals of opening the hips and relieving back pain. It's called "Easy Pose" (Sukhasana).
Easy Pose (Sukhasana)
While it sounds and looks simple, this pose is quite hard for people with tight hips. It will help to open the hips, lengthen your spine, and focus on calm breathing to alleviate discomfort. (Which will come in handy on the big birthday!)
If your belly is making it difficult to find a neutral posture, practice this pose with your back to a wall for support.
Cross the legs, placing the feet directly below the knees. Your feet will be further from your body than in a traditional cross-legged position. If you see a rather large triangle formed on the mat with the space your legs create, your positioning is correct. Rest the hands on the knees with the palms facing up.
Using the strength in your legs, press the hip bones down into the floor and lengthen the spine by sitting straight against the wall, pulling shoulders down and back.
Let the tongue rest on the roof of the mouth, soften the face muscles and close your mouth. Close your eyes, and inhale and exhale deeply and rhythmically through the nose. Try to hold the posture for five minutes, and begin feeling the relaxing benefits breathing can provide through discomfort.