Live in Colorado where MJ use is becoming more and more socially acceptable.
After full disclosure with my doctor's the advice was to stay off for a week pre op and at least until you were off the narcotic post op meds. Indicated there were some medical leanings that MJ may inhibit the receptors the pain meds act via. Though, during what my lady and I thought was one of the more amusing pre-op moments, the nurse shared that "if the pain meds don't seem to be sufficient, go ahead and smoke a bowl".