I'm going to break up with my 8 month pregnant girlfriend
If your girlfriend is pregnant, why would you leave her?
I just don't want to have children
Breaking up with someone who is pregnant with your child is irresponsible. You agreed to the child by being with her up to now, so follow through on your responsibility.
I'm going to go through with it anyways.
If you're fully committed to this, you better be prepared to pay some child support then.  Not doing so is gonna land you in a lot of legal trouble.