Curious about the traditional Catholic position on requesting an epidural to decrease the pain in labor. Is it considered morally wrong or even sinful?

I don't see how it could be considered sinful.  It's not really what was intended for birth, though, to be numbed from the experience of it.  It's also not good for the woman.  It also isn't good for the baby, who thrives on the hormonal connection between mother and child during the birth (as does the mother).  In general, it's not a good idea unless it's medically necessary for some reason, which it can be.

Having had the epidural for two births and then none for following births I would say that the epidural while good in the short term for pain relief , it dumbs down the bonding immediately after the birth.  From my own experience I thought that the natural birth with no epidural gives you such a high whereas with epidural there is a bit of an anti climax because you are pretty much the same as you were during the pain free labour.
I also was much more successful at establishing breast feeding than with the others.  Really made me appreciate that God created natural order and He knows what He is doing even if we don't.