Imagine, for a moment, that you are emergency medical personnel. You are working on the victim of a car accident, who is unconcious, and has no pulse.
At that moment - to the person you are working on - it makes no difference if you succeed. Since he is dead, he has no experience of your attempt to save him. It only matters to him if he wakes up. He's not going to put in a complaint if you don't succeed.
But if he does wake up, he might be incredibly grateful. He or she can possibly experience decades of meaningful life. Their dependency on others is morally irrelevant, or we would let people who cannot pay medical bills just die or parents abandon their children.
This seems to be exactly true of either fetuses or children in general: if they are created they can experience decades of life, possibly meaningful.
So the question is What is the difference between not having a child or refusing to call for aid when you drive by a car accident?
In both cases, there are potentially decades of life experience that are lost, whether or not there are rational decisions for those choices...