Well, one could go to the "Declaration" of scripture, the ten commandments: "Thou Shalt NOT kill!"
“When men strive [struggle/quarrel/contend/fight] together and hit a pregnant woman, so that her children come out, but there is no harm, the one who hit her shall surely be fined, as the woman’s husband shall impose on him, and he shall pay as the judges determine.
"But if there is harm, then you shall pay life for life, eye for eye, tooth for tooth, hand for hand, foot for foot, burn for burn, wound for wound, stripe for stripe.
Interpretation: If the child lives, then the husband still has the right to demand a fine for the premature birth. If there is injury - note that the text does not distinguish between mother or child there - then everything up to and including the death penalty is on the table.