Could the mother have claimed tax benefits for the fetus at the time of the injuries? Could she have had the state recognize her fetus as a human in any other way besides being penalized had she decided to abort?
If the fetus can not live on it’s own outside of the womb, that’s an interesting question.
But a fetus is not a human. I’m pretty sure at the three points you mentioned it’s technically not a fetus anymore according to medical science.
Edit: this incident pulls at our heart strings. I get that. He should be required to compensate and help with the care and medical assistance for the now human child. But no child was injured at the time of the multiple assaults on the mother. We need to be consistent and rational while also having empathy. Calling fetus’ humans does not accomplish this.