On the other side of that argument, a fetus does not have the higher brain function or consciousness that would allow it to experience pain. When an adult is put under general anesthesia for surgery we do not generally consider them to be "experiencing pain" even though the body is still reacting the damage as though they were conscious. They still have brain function, they temporarily lack the higher brain function required for the meaningful experience of pain. A very similar argument could be applied to a fetus.