My wife had it. It is a surgical procedure and done under general anaesthetic. I dropped her at the hospital at 8:30am and picked her up again in the afternoon. It's not a major thing, just slightly uncomfortable I think. The point is to check if a path exists between ovaries and womb. I expect the blood tests are to see if there are any obvious problems there so I unless they show something glaringly obvious it's not going to change the need for a laparoscopy. I presume this is because you've had trouble conceiving? That's certainly why my wife had it.
If it's any help, three years down the line we now have two bouncing healthy baby boys (separate pregnancies, not twins).