ok, here's my $0.02.
i understand that you feel you've really fucked up. enough of it though. i learned years ago that when i fuck up, just admit it, and then stop dwelling on it. move on, solve the problem.
if i were you, i'd get as many opinions as possible from highly qualified professionals. tell them EVERYTHING that you and your girl have taken, whether it be legal or not. this includes any recreational drugs and/or alcohol. seeing as how there's some AAS involved, anything and everything is going to have an effect on this.
i don't know anything about AAS, to be quite honest with you. i have no clue what winstrol does. i do know, however, that anything that's not natural for a fetus can have seriously bad effects. however, a normal, healthy child could result from this.
everyone has their opinions on abortion, and yes, it is a very political issue. if i were you, i'd ask yourself this. if the child is going to be plagued with a life of medical and mental complications because of things that the mother has taken into her body, then it is probably for the best to terminlate the pregnancy. if, however, that is not the case, then step up and take responsibility for your actions. i was faced with a similar situation where the life of the mother could've been put into danger. both the mother and the child came out AOK, and i've got a wonderful (well, not all the time, but you know what i mean) 3 1/2 year old son.
the decision is not only yours, but hers, as well as the decision of the LAW. check your local and state laws pertaining to abortion to ensure anything you do is legal.
good luck.