A comprehensive study of abortion in America underscores a striking change in the landscape, with ever-fewer pregnant women choosing abortion and those who do increasingly opting to avoid surgical clinics.

The number of abortions has plunged to 1.2 million a year, down 25% since peaking in 1990, according to a report released today -- days before the 35th anniversary of Roe vs. Wade, the Supreme Court ruling that legalized abortion.

In the early 1980s, nearly 1 in 3 pregnant women chose abortion. The most recent data show that proportion is closer to 1 in 5.


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"That's a significant drop, and it's encouraging," said Randall K. O'Bannon, director of education and research for the antiabortion group National Right to Life.

Women looking to end early pregnancies are gravitating to medication abortions, in which they take two pills under a doctor's supervision to induce miscarriage. This approach lets them avoid surgery -- and the protesters who often picket clinics -- and expel the embryo in the privacy of their homes. The Food and Drug Administration approved the pills in 2000 for use through the seventh week of pregnancy.

By 2005, the most recent year covered by the report, the pills accounted for 13% of all abortions.

The research was conducted by the Guttmacher Institute, a New York-based nonprofit that focuses on reproductive issues. The institute supports abortion rights and has received funding in the past from Planned Parenthood. Abortion opponents, however, generally view its statistics as reliable.

The Guttmacher report came to no conclusions about why the abortion landscape had changed. But that didn't stop activists on both sides from speculating -- and using the data to press their political agendas.

Abortion rights advocates suggested women may be avoiding unwanted pregnancies, thanks in part to the morning-after pill, emergency contraception that is sold without a prescription to women 18 and older.

Led by Planned Parenthood, activists have pledged to spend much of 2008 lobbying for laws to make all forms of birth control cheaper and more widely accessible. They also plan to push states to require sex-education classes that teach teens about contraception.

A political tactics manual recently developed for Planned Parenthood asserts that voters respond well to such issues -- especially when they're framed with buzzwords like "prevention," "protection" and "personal responsibility."

Dwell too much on abortion, and the broader liberal agenda will bog down, said Kathy Bonk, a consultant who developed the strategy. "It matters where you start the conversation," she said. "If you start on abortion, you don't get off abortion."

Conservatives, by contrast, are eager to keep the focus on abortion.

They contend that the more women learn about the procedure, the less likely they are to choose it. The rapid growth of crisis pregnancy centers -- which offer free diapers, parenting classes and other support -- has helped cut the number of abortions, they say. But just as important, in their view, are laws in more than 30 states mandating counseling before an abortion.

Some of the material given to women at such sessions is false or misleading -- for example, warnings that abortion raises the risk of breast cancer or causes post-traumatic stress disorder. Abortion rights supporters also object that many of the counseling brochures use photos of fetal development through nine months, though 90% of abortions take place in the first trimester.

Abortion opponents view such material as a vital tool to turn women against abortion; they plan to lobby to expand this type of counseling.

"We are making progress, state by state and law by law," said Denise M. Burke, vice president of Americans United for Life.

Some of the biggest drops in the abortion rate, however, have come in states that do not impose tight restrictions.

Oregon, for instance, was rated this week by Americans United for Life as the nation's "least pro-life state," yet its abortion rate dropped 25% from 2000 to 2005 -- more than any state except Wyoming.