Although they have seen small victories, in the form of parental notification or informed-consent laws, anti-abortionists also have had major setbacks, such as the Supreme Court's decision just this past summer to throw out a Nebraska law prohibiting partial-birth abortion.
But as some see it, the defeats have given the movement renewed momentum, just as an avowedly anti-abortion new administration has come to power in Washington.
Cathy Cleaver, director of planning and information for the U.S. Catholic Bishops' Secretariat for Pro-Life Activities, said the Supreme Court has handed the movement a "particularly bleak" outlook, but it has not succeeded in defeating those committed to the cause.
If anything, she said, "the court is reinvigorating the U.S. Catholic bishops, who are rededicating themselves" to anti-abortion efforts with all the more fervor.
The bishops approved a statement at their general meeting in November called "Abortion and the Supreme Court: Advancing the Culture of Death," in which they spoke of their commitment to reversing Supreme Court decisions legalizing abortions.
The focus of the U.S. bishops on this anniversary of Roe v. Wade has not changed, Cleaver said.
"The bishops' main goal has been to overturn legalized abortion, and each year new opportunities present themselves to do that," she told Catholic News Service. However, she said there was "not a realistic shot" at immediately overturning the Supreme Court's 1973 Roe decision.
But Cleaver said the bishops were committed to stopping abortions even through "seemingly small measures" such as opposing the use of federal funds for embryo research and supporting the Mexico City policy, which denied U.S. foreign aid to programs overseas that promote abortion.
Over the years the anti-abortion movement, which supporters often call the pro-life movement, also has pushed for parental notification when a minor seeks an abortion or informed consent laws to make sure women seeking an abortion understand all that's involved. Today about 20 states have enacted such legislation, and the U.S. Supreme Court has upheld such measures in limited form if they include a provision for judicial waiver.
Abortion foes also have worked for a ban on partial-birth abortion, but in decisions leading up to the Supreme Court's consideration of the issue, federal courts struck down several state laws banning partial-birth abortions. President Clinton twice vetoed a federal ban on the procedure.
Other efforts by abortion foes include trying to stop approval of the "abortion pill" known as RU-486 in the United States and fighting use of the morning-after pill. But in September the Federal Drug Administration approved RU-486, and the American Medical Association recently said it would consider recommending over-the-counter sales of the abortifacient morning-after pill.
Nellie Gray, organizer of the annual March for Life in Washington, continues to put most of her focus on overturning the Supreme Court's decision legalizing abortion, telling CNS she didn't "have any doubt" it would happen, she just didn't know "how or when."
And meanwhile, she is not about to back down.
Not everyone shares her zeal though. Despite the crowds that show up for the annual march she has been organizing for nearly three decades, she said, she senses apathy in the pro-life movement partly because "it's been going on so long."
This "incremental approach," she said, "did not develop into a stepping stone" to make abortion illegal "but rather, made a pocket of quicksand for the pro-life movement."
As she sees it, the only way for the movement to gain success and ultimately prevail is for it to take on a completely uncompromising position.
She would not speculate on whether the new Bush administration would give a boost to the movement, but noted that since George W. Bush "said he was pro-life on the campaign trail," he was invited to attend the annual march.
It was not immediately know whether he would attend. However, anti-abortion activists are encouraged by Bush nominating Wisconsin Gov. Tommy Thompson to be his Health and Human Services secretary, and former Sen. John Ashcroft to be attorney general. Both are staunch abortion foes.