Most of the time baby gets put on a towel on top of you (well 6 of my 7 did). Its really only if you are naked that you will get gunky if you go for immediate skin to skin. If you dont want to have baby handed to you with all the birth gunk all over them, express this to your mw when you go in to have your baby. You will be surprised at how much changes when you are in the moment though. When we arent in the situation, just thinking about it we think ewwwwwwwww, at the time theres so much going on you will probably find alot of stuff that the thought of it bothers you now, wont bother you then. In fact you probably wont even notice it, when you are in labour, giving birth and just after delivery.