Oh, but unborn babies have the prerequisites for life!
They can't survive in the world because they belong in the uterus, where they will grow and flourish. They have an umbilical cord and have living cells, and will grow to become a baby when they're ready. Violently taking the prerequisites away from them is not okay. They are a human.
Now, I used the arguement that the unborn are human, which you seem to have supported in a comment above here. You also argued that "half of all pregnancies end in a miscarriage", which justifies abortion by it being natural. But just because something naturally happens doesn't mean that it's right for us humans to do. We know better. Murdering a helpless developing baby because it is inconvenient isn't right.
In addition, a miscarriage usually happens in a woman's body because the baby isn't developing right and it will kill her, which would also kill the baby. So the body terminates the baby. A miscarriage is the trolley problem, one or two die. You know the answer.
I know this isn't sufficient to answer all of your arguements. And I hope you respect this reply a little more than the meme comments above this. If you want to contest this, or you still have questions, feel free to poke at this!