what i mean is that literally he needs to penetrate in you for you to get pregnant. what if he did not penetrate but his sperm is on your undies, will you get pregnant by that? or the sperm needs to travel by fluid for you to get pregnant. i'm really confuse about this coz my friend is asking me this. and i don't know what to say to her. so i think this is the best site to ask about this. so is it true that a sperm can travel through ur undies?