This might offend some parents.  I can't tell you what to do with your life, and I'm not trying to make anyone feel bad about their decisions to raise offspring.   
They say the love a parent has for a child is unlike anything I'll ever experience.  "They", meaning anyone who finds out that I'm married, often say things like that to me.   If they don't dismiss my opinions as something I'll eventually change, because of hormones or some feeling of lack of purpose in my life, they often ask "why not?".    I didn't realize how taboo it was to not want kids. 
I have personal experience growing up... I just finished actually.   Well I shouldn't say that... I learn new shit everyday.   But personally speaking, growing up to discover all that's wrong with this world was a very disappointing thing to endure.  My hate for the human race grows to this day, and there isn't a lot of positivity to hold on to.   I have some things, like nature, but I know that nature is suffering because of us, so, as beautiful as it is, I know that it's not always going to be there to comfort me. 
I wouldn't wish this world upon anyone.  I especially do not plan to purposely expose my own flesh and blood to it.   How can I teach a child about the world without negative impact?  Lie?  That only works for so long, and could lead to even further disappointment when they eventually find out that Santa Claus isn't a real person.   I could tell them the truth, but I can't teach them to cope, because I can hardly cope myself.  I've accepted the lack of jolly Ol Saint Nick, but I haven't accepted the shit that isn't within my control.  Everything is fucked... and there's no escape except death.  I don't plan on killing myself, however I am very passionate about change that isn't going to happen.    If Martin Luther King couldn't rid the world of racism, who am I to think I, or my children, could solve one of the world's pressing issues?   Even when there is a solution, when do we ever see it trump the bottom line? 
I'm reasonable I think.  I won't try to convince myself that I would be any better than any parent.  I won't assume that my children will never grow up to be assholes.  It would be wrong for me to do so.  I can hope for the best, but I cannot know.   I can however go from what I do know, which is that my siblings and I have all grown to be very very different people, even though we were all raised in the same home, and do not vary much in age.  This tells me that a parents influence is slight, and does not have the life-scheduling effect many parents aim for.   
Maybe one day I will adopt.  There are many kids out there that need parents.  I didn't make their lives, but I can try and make it decent.  This way, I won't feel responsible for overpopulation, as I won't be contributing to that problem.   I can know the love between parent and child, and I can try my best to bestow a good person upon this society.... God knows we need that.   However, I could never live with the guilt of creating life.  As much as I would care for my children, I would feel selfish for wanting one, while knowing the risks.  No matter how improbable, there are risks, ones that I am not willing to take without a really good reason.