He is 100% pro life. That is the pro life claim. That is what the legislation they are trying to pass claims.
Go read the Sanctity of Life Act. It claims the zygote is a Homo sapien/ Person = living human such that it should have the same rights as citizens.
Carson is against abortion ... not just abortion after the second trimester or some reasonable position where a legitimate argument can be made that indeed it is a person.
Is a zygote a single cell? No. Why are you pretending it is? Can't support your lie? Go to a dictionary and look up "single".