I had a severe sprained ankle and now I need surgery on it to stabilize it. However I am 17 weeks pregnant.?

Will I have to wait until the baby is born or can they do it now? It's been over 3 months since it's been sprained. It's getting worse not better. Now I'm back on crutches (Dr's order on Friday May 27, 2011). I have to see a potiatry tomorrow. What's going to happen?