I had it in the last 5 weeks of my 2nd PG, but it wasn't diagnosed. I know what the pain was after having it during my 3rd PG.
For my 3rd PG I had it come at about 20 weeks. It got really bad for bit then it kind of got a bit better for a couple of months. By the end of my PG it was bad again. I could barely walk in the morning and one I felt that front joint clunk after a few mins of hobbling it was reasonable for the rest of the day.