Here's what I found in a google search:
"Is there any treatment?
Unfortunately there is no way of tightening the ligaments again during pregnancy, so no treatment will be able to cure SPD. This includes any sort of osteopathy, reflexology or acupuncture. However, after the birth the body stops producing the hormone, so the ligaments tighten up and (for the majority of women) the symptoms gradually disappear.
So what can be done?
The most important thing is to avoid doing anything that aggravates the condition, such as standing on one leg.
Sit on a chair to get dressed.
Be very careful to get into a car by putting your bottom on the seat first, and then lifting your legs into the car.
When you get out, lift your legs onto the pavement and then lift your bottom off the seat.
If you go swimming, don't swim breaststroke.
Always turn over in bed with your knees firmly together.
Make sure you get a rest (in bed) every day.
If you already have a child, you will need help, as you will find it difficult to lift him or her."
For what it's worth, I had cessation of symptoms within 4 days of my twins being born. So hopefully you'll find relief quickly after birth, as well. Sorry you're experiencing SPD. I wouldn't wish it on my worst enemy (well....maybe.....