Hello mama-to-be
Congratulations on your pregnancy...how exciting! I thought I'd share a little personal experience and add in a few suggestions from a TCM (Traditional Chinese Medicine) perspective.
There are lots of great yoga postures to help open the pelvic cavity and increase mobility in both the hips and pelvis. Postures from the yin repertoire that I found useful in my pregnancy were postures like squats (with or without blocks/props), butterfly, 1/2 butterfly, dragonfly, dragon series, swan (some of which I had to find creative ways of using props). Table top moving the hips in circles (back to front) is great for low back pain and labouring women often find themselves in this pose to help ease discomfort.
My only caveat that I learned the hard way was because a pregnant woman's body produces a hormone called relaxin, I found that early on in my pregnancy (25 weeks) I lingered around a little too long in the dragon series and couldn't walk for weeks and weeks without feeling unstable and in pain. What I often suggest to my pregnant students is to not go as far as they know they can but instead try and take the time to connect with baby. Everyone is different as far as how long to hold a pose but maybe try doing 1-2 minutes and seeing how your body responds. Intention is key so even while you hold back from going to your deepest depths try perhaps imagining that the uterus is being nourished with blood and that your ligaments and pelvis are becoming more open to accomodate a healthy birth. Also try and keep the jaw relaxed as this will also help keep the pelvis relaxed.
I treat a lot of pregnant women with acupuncture and not only does it help increase blood flow to the uterus, it also can help with many pregnancy related issues (ie. constipation, low back pain, hemorrhoids, anxiety even to help induce labour if you are past due). This website is a great resource for pregnant women looking to find some information from a TCM perspective on acupressure points you can administer on yourself (which you can try while holding in some yin postures), dietary advice, post partum information etc...
http://acupuncture.rhizome.net.nz/
Yin yoga was a god send after I gave birth as it helped me find some sense of calm in my mind and body amongst all the noise! All the best in this last leg of your pregnancy and here's to a fast, relatively painless, healthy labour and birth!
Cathy:)