Pro-life is the name given to people or organizations who defend the rights of the unborn child, and who oppose abortion.
Due to rulings by the U.S. Supreme Court, the United States allows abortions at virtually any time in pregnancy. Many state governments even pay for abortions using taxpayer dollars.
In American politics, the Republican and Constitution Parties are often associated with opposing abortion and believe it should be illegal. The Democratic and Libertarian Parties both support the rights of women to have abortion and oppose legal restrictions (libertarians themselves are divided on the issue). The Democratic Party supports taxpayer-funded abortion as well.
The phrase "pro-life," especially in the Catholic Church, may also include similar issues, such as the death penalty and euthanasia.
Ironically, some fundamentalist pro-lifers have previously bombed abortion clinics, sometimes killing doctors and other staff in the process [1]. Most pro-lifers, though, denounce these acts of violence in favor of more reasonable methods of disposing of women's rights.