Kapotasana (Pigeon Pose)

To begin the pose, step forward with your right foot and lean into a lunge position, keeping your back leg straight behind you.
Slowly move your right foot to the left side and drop your knee to the right onto the ground while flexing your toes outward. Try to keep your shin perpendicular to your back leg but if you feel discomfort, bring your foot closer to the groin area.
Square your hips by transitioning your right hip back and your left hip forward. (If your right hip drops too much use a blanket to prop it up to keep your hips level.)
Your left leg should still be stretched out straight behind you, but now resting on the ground.
As you sit in this pose be aware of your breathing - inhaling and exhaling deeply - and imagining all the tension in your buttocks and hips to be spacing out and relaxing. A myriad of emotions and sensations will arise the first few times you practice this pose. It's important to stay focused as you observe these changes while they pass through you.
You will find that the longer you sit in this pose the more it will deepen; releasing tension that you didn't even know existed in the depths of your buttocks and hips.
Stay in the pose as long as you need and then repeat with the left leg.
To Extend the Pose: While you are in the pose, slowly bend forward to lie on top of your bent knee, bringing your face toward the ground.

Learn about the benefits.

** If you have knee injuries such as damage to the ligaments or tendons, lift the hip of the back leg a little bit. Generally though, knee problems often stem from tight hip muscles so the pose may decrease knee pain.

Utthanasan (Squat and Rise Pose)

Stand up straight with your feet about three feet apart, with toes pointing out.
Hold your hands in a prayer pose in the middle of your chest.
Keeping your spine straight, bend at the knees and lower yourself until your buttocks are only inches from the floor.
Slowly rise to a standing position.
Repeat as desired.

Benefits:
Strengthens and tones muscles in the knees, legs, middle back and buttocks.
Increases circulation in the legs and pelvic region.
Stretches buttocks and back muscles.
Increases balance and concentration.
Opens the pelvic region for easier delivery.

http://www.parentingweekly.com/pregnancy/breathingspace/vol26/pregnancy_exercise.asp

Spinal Breathing

Find a wall or flat surface to provide back support during this advanced pranayama technique.
Close your eyes and your mouth. Slowly and gently inhale and exhale through your nose. The breath should be deep but not forced and should fill your abdomen up through your chest to the top of your collar bone, before retreating during the exhale. Slowly repeat this a few times.
As you inhale, focus your attention and imagine there is a tiny tube or cord that originates at your perineum and stretches up through your spine to the stem of your brain and terminates at the center of your head. Once your attention reaches your head, imagine a tiny nerve turns forward to reach the point between your eyebrows.
With each slow inhale, imagine energy funneling up from your perineum up to the point between your eyebrows and then back down again to your perineum. Repeat this with each breath.
This exercise should be done for a few minutes before meditation. Remain seated when you are finished with the exercise and begin meditation immediately.

Benefits of this exercise: http://www.parentingweekly.com/pregnancy/breathingspace/vol14/pregnancy_exercise.asp

Lotus Pose (Padmasana)

The Lotus Pose is said to have been routinely used by Buddha and is a popular meditation pose. It may be uncomfortable at first until your ligaments extend. It's a common misconception that meditation should be done in the Lotus Pose, so if it is too difficult, any other seated pose will work well. This is one of the basic yoga postures, so take your time becoming comfortable in it.
How to do it
Bring your right foot onto your left thigh. Bounce the right knee and, if it touches the floor with ease, bend your left knee and grab your left foot with both hands and place it on your right thigh. Your hands should rest on your knees, either open or forming a mudra.

Benefits of this pose: http://www.parentingweekly.com/pregnancy/breathingspace/vol11/pregnancy_exercise.asp

Kapalabhati

Kapalabhati is a cleansing breath that literally translates as "skull that brings lightness." Use it to clear a foggy or heavy head or when you have mucus buildup in your air passages and tension or blockages in your chest. It can also help with sinus issues, such as numbness around the eyes.
During this breathing exercise, the breath is deliberately sped up using only diaphragmatic (abdominal) breathing. Each breath is short, rapid and strong as the lungs act as a pump to expel air from the lungs and remove waste from the air passages.
It is important to do this exercise carefully while sitting. If you are pregnant, skip the breath retention step, as holding your breath can harm your baby. This exercise may create tension in the breath and cause dizziness, so always end your practice with some deep, slow breaths.
One Repetition:
Begin by breathing normally twice. Inhale, and then exhale while pulling in your diaphragm. Repeat this 20 times, maintaining a steady rhythm and emphasizing the exhale each time. Follow this by inhaling and exhaling completely. Now, inhale and hold your breath for as long as is comfortable (skip this step if you are pregnant). Slowly exhale.

Learn more: http://www.parentingweekly.com/pregnancy/breathingspace/vol10/pregnancy_exercise.asp

The Lion's Roar during Labor

Pratyahara is the act of directing your attention to a "disturbance." Instead of trying to avoid or suppress pain, accept it and experience it. As you get to know it, it will no longer feel dangerous. The pain may not disappear but the fear of it will. Fear and stress can complicate the birthing process and put your body through more suffering than necessary. Once you can accept the pain and allow yourself to experience it, birth becomes a powerful experience. Some women have said they were able to feel each movement of their uterus through this technique, while others have said they were able to allow the forces of nature to work.
The Lion's Roar
Many women have found this vocal toning technique to be very beneficial during labor. Open your mouth and stretch your tongue far out. While exhaling, make a relaxed, deep sound. This will automatically cause your body to respond and begin to relax from your groin to your pelvic floor and up.

Read more: http://www.parentingweekly.com/pregnancy/breathingspace/vol12/pregnancy_exercise.asp