I have always been a "landing strip" kind of woman.
So, I have been able to keep up with shaving the sides (though certainly not very well at this point since I have to do it mostly blind). Once I got to the point where I couldn't see to be able to trim the strip, I had DH do it. Only with the trimmer, though, I don't let him come at me with a razor. He does a really good job, almost too good and brought it down a little shorter than even I normally would, but I wasn't about to complain.
My hair isn't growing out of control this pregnancy, so I've only had to have him do it once, though I will have him do it again soon.