When I had mine done, hospital said not to bd at all as if preg then it could be flushed into tubes and could get ectopic preg thats what they are covering themselves over. What happened with me is that I was booked for my HSG and on the day I went along called my name out, went into little room, got gowned up, nurse came in and asked me if we had had intercourse b4 this proceedure-well said yes but with condom cos I thought that this would be ok and hubby said it was ok. How silly was I to be believe this. I did not read the sheet properly that the hospital had given me and the nurse said she needed to speak to the doctor who was doing proceedure. So off she went then came back into the room and said that I couldn't have it done. Well I was distraught as I had just started a new job and it was so hard to take the time off and to coordinate with everything like no af etc. I was sobbing like a baby to the doctor, they jsut said that they would have to reshedule it, so had it at a later date.
Sorry to say this to you, I mean maybe your hospital does things differently but just thought would tell you what happened with me. Good luck anyway! Maybe check with them!