I saw a chiro through my last pregnancy until 19 weeks when I moved away. The adjustments are gentle but very effective, and made a huge difference to my pelvis. I thoroughly recommend you at least give it a try, it may make a huge difference to your pain levels.
Just as another option up your sleeve Fiona, another thing you could consider in an osteopath. I saw one during pregnancy (not for any serious issues like SPD) but just to help maintain good alignment and positioning. A lot of my pilates clients have a great deal of success with ongoing osteopathy treatment along with exercises specific to their particular condition.
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