Anyone who worries about the what impact them having a child might have on the planet are exactly the peope who should be having children!
Why? Because these people are clearly not stupid and the world needs more offspring from intelligent people.
Around the world, we have far too many uneducated, poverty stricken masses replicating at the same rate as rabbits. Many of these offspring die in hideous circumstances, but this is not something new. People have many children, fully aware of the mortality rate. It's a like throwing mud at a wall - you hope some of it will eventually stick..a bit like the rest of the entire natural world!
Even parts of the UK has a problem with women busily pressing out babies safe in the knowledge that they haven't a cat in Hell's chance of bringing them up without substantial government handouts, knowing they can demand a free home and food. Often the mother has multiple partners and doesn't even know who the father is. What a miserable state of affairs and a wholly wrong environment in which to to bring another human into this world!
In the developed world, we have far too many people requiring free stuff and that there are not enough people paying for it, but hey, that's socialism for you!
On the subject of having an unwanted pregnancy, i'd suggest that the OP made his bed and so should now lie in it!
It won't be the freedom sapping experience that he perceives. Children, whilst a massive responsibility, provide a great deal of joy, especially in the early years.
I feel a bit sorry for those who have the means, but have made a conscious choice to go without children, purely so they can continue to do as they please. Their lives will never be as full as those with an extended family, especially in later life.