Teenage talk of abortion

Me, mi boyfriend and mi sister and her boyfriend had talked about abortions. We feel that we are all too young to have babies. we're only between 17-19. The guys thought that if a mistake happened, one time wouldn't matter. Mi 18 y.o. sister was stuck in the middle. and i said that even though i am 18 y.o. and it would be a mistake i wont kill something thats growing inside of me. its just really immoral (to me). the guys think them unborn so they are not "technically" alive. but i argue that i have very strong beliefs and im willingly to take responsibility for mi irresponsible acts. i feel that apart of me would also being dying for what im letting happen. what are your views everyone...?