Dialogue before sex... oh yes, certainly... after though, no way.
After sex it's a token cuddle, then I just rollover and go to sleep.
I think every writer who believes they can pen a convincing sex scene, should first imagine their parents as the characters in the story. For those of us who had the unfortunate experience as kids to at one time or another burst in too early in the morning to wake mom up so she could make breakfast, only to see mom and dad grinding it out... sex is better left to the imagination, and not written on the pages of a book.