There appears to be some new controversy over whether or not unborn babies feel pain, and when. From the article:
A review of medical evidence has found that fetuses likely don't feel pain until the final months of pregnancy, a powerful challenge to abortion opponents who hope that discussions about fetal pain will make women think twice about ending pregnancies.
Critics angrily disputed the findings and claimed the report is biased.
"They have literally [literally? -- MW] stuck their hands into a hornet's nest," said Dr. Kanwaljeet Anand, a fetal pain researcher at the University of Arkansas for Medical Sciences, who believes fetuses as young as 20 weeks old feel pain. "This is going to inflame a lot of scientists who are very, very concerned and are far more knowledgeable in this area than the authors appear to be. This is not the last word _ definitely not."
As I pointed out two years ago, it doesn't matter if unborn babies feel pain.
The real question isn't whether or not the baby can feel pain, but whether or not the baby is a human being with a right to life. If not, then it doesn't matter whether there's pain involved -- we hurt non-human things all the time when it suits our purposes, and most people don't have a problem with that. If the baby is a person then it still doesn't matter because you can't kill people, painlessly or not.
No matter what you think about abortion, the presence or absence of pain is irrelevant.