By Carol Gray, LMT, CST, RPYT, ERYT-200 How it All Starts Pain in the posterior pelvis is common during pregnancy. It typically begins in mid pregnancy. Although, it can start at any time. Sometimes it goes away during pregnancy. If it does, that usually happens in the third trimester. Other times it persists long after the birth. Your mileage may vary. Your SI Joints This pain often comes from the