I could see a reasonable harm reduction case to be made, but I’ve literally never met a pro life person who supported harm reduction. Maybe they exist, but not in large enough numbers to make a difference here.
The harm reduction case is this: rape and incest are traumatizing enough that trapping a hormone flooded adult with the incredibly annoying and helpless evidence of that trauma could lead to a much worse scenario (the mother also dies, additional children die, the baby is slowly neglected to death, etc.).
I don’t know how good an argument that is, but I can at least understand it.