Did you know that twenty years ago, doctors performing surgery on some preemies did not use anesthesia, because they were convinced the babies could not feel pain? Now we know that they do, as do babies in the womb as young as 20 weeks — although there are of course those who dispute that, including one doctor who has provocatively asserted that babies can't consciously feel pain until their first birthday.
This plays into the battleground over abortion, as pro-life forces strive to educate women and clinic patients specifically about fetal pain.