Drinking and smoking are legal, for now anyway. While they have some bad effects on the unborn, Meth is a little more nasty plus it's an illegal drug. I shudder to think what it does to a fetus.
My wife and I are going thru adoption classes now. A lot of the kids up for adoption are fetal alcohol syndrome kids. It's the worst of all of the drug/pregnancy interactions. It never gets better. The crack babies usually get over it and end up pretty normal. I don't know about meth. But from the info I have seen now, drinking during pregnancy IS child abuse.