Snb - welcome to the forums - you have come to a good place. I don't think you will find anyone here that will judge you, especially since you are trying to do the right thing for yourself and your unborn child.
I would start with your OB/GYN for advice, hopefully, if they do not feel qualified to advise you on tapering off the Percs - they will refer you to another doctor.
Take care and keep coming back,
Jim