well there is a new thing called the female condom, i can tell you IMHO its like having sex with a ziplock baggie.
Thats basically all it is.
It looks like an open ended baggie that she inserts and leaves the opening sticking out.
there is also foam and other forms of contraception.
but the only true way from getting preggo is abstinance, but since thats out, when your getting ready to cum, shove it in her mouth.
Its high in protein and less filling then an energy bar. lol