Great question: I posed this to a pre-natal yoga group I'm in (www.mayoga.com - great blog with more tips) and here's what was recommended:

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  I recently had a student who did Warrior II during transition! Most laboring women I've come across seem to prefer more free and open movements that include swaying, circles (leaning on a birthing ball) and hanging.
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  One I like is a belt over the top of a door (make sure it's super secure!) and then hold the belt, one side in each hand, and hang and sway in a squat. Feels great, gets energy moving down and out... I'd love to hear what other people found themselves wanting to do!
  
  
  
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  For me squatting was fabulous. Also ~ lots of rocking/swaying while leaning on a ball or counter.
  
  I also found it helpful to use Ujjayi breath ~ releasing tension throughout but specifically into the pelvis/hip areas.
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  I like cat cow, gives the baby room to get nice and low.

I hope this helps! Post any additional comments or questions here!

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