The state currently bars abortions 24 weeks or later into pregnancy.
Backers of the bill cited progress in medicine that allows premature babies to survive earlier in pregnancy than before.
The bill would have preserved current exemptions for when a mother's life is at risk, or if she is at risk of a serious permanent injury, the Associated Press reports. It would not allow exemptions for rape, incest, or fetal abnormalities.
Dawn Keefer, R-York, said the issue should not be framed only in terms of women's rights. Rather, she asked, "what about the rights of those pre-born women in the womb being exterminated?"
Rep. Mary Jo Daley, D-Montgomery, characterized the bill as an attempt to control women "by imposing the views of some legislators on women, and I think that's wrong – that's morally wrong."
The dismemberment abortion ban would have in effect banned dilation-and-evacuation abortion, the most common method of abortion in the second trimester of pregnancy.
"Dismemberment abortion is completely inhumane, it's barbaric," said Rep. Kristin Phillips-Hill, R-York.
Federal legislation to bar abortion after 20 weeks has made some progress. On Oct. 3 the U.S. House of Representatives passed the Pain-Capable Unborn Child Protection Act late by a vote of 237 to 189, largely along party lines. It was expected to fail in the Senate.
Dannenfelser, however, claimed, "Momentum is building to pass a national ban on late-term abortion more than halfway through pregnancy."
An override of the governor's veto would require a two-thirds vote from both legislative houses of the state of Pennsylvania.