Thirty years after the Supreme Court ruled that women have the right to terminate a pregnancy, both sides of the fiery abortion debate are still battling over what's best for women and their unborn children.

Wednesday marks the 30th anniversary of Roe v. Wade, the decision that made abortion legal. While pro-abortion groups fight to ensure that the decision is never overturned, anti-abortionists continue to maintain that the practice constitutes legalized murder.

Groups from both sides planned a myriad of events Wednesday to support or criticize the decision. But this year's demonstrations and debates are fairly typical of the past 30 years.

The all-male Supreme Court ruled 7-2 on Jan. 22, 1973, that a woman's right to choose was based on her constitutional rights to personal liberty, which entails her privacy. The decision overturned state laws banning abortion.

Since then, an average of more than 1 million women a year have had abortions, making them one of the most common surgical procedures in the United States.

But the decision's future may be uncertain.

The recent conjectures about the future composition of the Supreme Court and recent limits placed on abortion in 34 states may be signs that Roe vs. Wade may not reach maturity.

"I would give anything, I mean, I could rest peacefully, I really believe if Roe versus Wade was overturned," said Norma McCorvey, the formerly pro-abortion, formerly anonymous Jane Roe in the case.

President Bush is staunchly opposed to abortion, but he has never been tested on the topic. Abortion supporters fear that with an aging Supreme Court bench, a Bush selection of a replacement justice could shift the debate and the law.

"I think any vacancy with the prospect of a Bush nominee jeopardizes Roe v. Wade," said Nan Aron, president of the pro-abortion rights Alliance for Justice.

Abortion is a source of division in the Supreme Court, which favors a 5-4 split permitting the practice. Justice Sandra Day O'Connor is the swing vote in favor of abortion rights.

Pro-abortionists fear that if she retires, Bush will likely choose a nominee who opposes abortion rights. O'Connor, 72, has served 21 years on the court.

"It's in the greatest danger it's ever been in," Feminist Majority President Eleanor Smeal said of the Roe decision. "You're one vote away."

Only current Chief Justice William H. Rehnquist, 78, sat on the court in 1973, and he was one of the two dissenting opinions. Should he retire, those who oppose abortion fear Bush may be pressured to choose a moderate to replace him.

Conservatives say they would oppose, for instance, the president's friend and White House Counsel Alberto Gonzales, who while a member of the Texas Supreme Court, voted to allow a teenager to get an abortion without parental consent.

"For all the pro-life groups, Judge Gonzales is probably a nonstarter as a nominee," said Richard Lessner, spokesman for the Family Research Council.

"It would be absolutely a tragedy if he were nominated," said American Life League President Judie Brown.

Abortion foes would prefer J. Harvie Wilkinson, the chief judge of the Richmond-based 4th U.S. Circuit Court of Appeals, or Samuel A. Alito of the Philadelphia-based 3rd Circuit.

Theodore Olson, the government's solicitor general and the lawyer who argued on behalf of Bush before the Supreme Court following the disputed 2000 Florida recount, is also popular among anti-abortion activists.

Although neither O'Connor nor Rehnquist has indicated retirement is on the way - and likely would not make a move until after the 2004 election - all sides agree that whoever is nominated to become the next judge will face a tough, partisan confirmation in the Senate, in which abortion will be a central issue.

That could be the reason that Brown's American Life League is putting pressure on Democratic Catholics in Congress to vote in sync with their religious tenets.

The group is launching an ad campaign to coincide with the anniversary of Roe and follows a decree by Pope John Paul II last week that demands Catholic lawmakers vote in concert with their religious values.

The ads are expected to slam a dozen Democrats, including Sens. Ted Kennedy and John Kerry of Massachusetts, for "flagrantly ignoring" their religion and perpetuating "the current culture of death."

"This crusade and the ad campaign are designed to ... demand that they either recant their openly pro-abortion stance or cease claiming to be Catholic," Brown said.

Conservatives say they are looking forward to a vote this year in the Republican-led House and Senate that would ban so-called "partial-birth" abortions, which take place in the last trimester of pregnancy. Bush has said he would sign the bill banning the practice.

Though no votes are scheduled yet on the topic, advocates on both sides of the battle say they expect that it won't be long before the law heads to the Supreme Court.

Aside from the religious-based and judicial battles brewing, women's groups say legislators cannot deny women the fundamental right to make choices about their own bodies. They argue that any effort to undermine Roe v. Wade is an attack on civil rights.

"Roe v. Wade is a piece of a much larger issue about who should make certain decisions and how much autonomy should women have," said Sarah Weddington, the attorney who won the abortion case in the high court.

"If women can't control their reproductive lives and the timing and spacing of their children, we are unable to control anything else about our lives we have," said Kate Michelman, president of NARAL-Pro Choice America. "We are at the whim of our biology."

But others say women's groups undermine women's rights by choosing to focus on this fight.

"I think it's very unfortunate that the feminists have made the right to abortion as their central and number one example of what they mean by women's rights," said Phyllis Schlafly, head of the conservative group, the Eagle Forum.

Polls show that a majority of Americans support abortion rights, but that support is highest when a woman's life or health is in danger or there is evidence that the baby will be physically or mentally impaired.

According to a Pew Research Center poll of 1,218 adults last week, six in 10 oppose the Supreme Court completely overturning the high court's decision. But a Gallup poll of 1,002 adults taken at the same time, shows that 57 percent said abortion should be legal only under some circumstances.

Fox News' Major Garrett and the Associated Press contributed to this report.