By Karen McVeigh, Guardian UK

Americans United for Life campaign to undo on a state-by-state basis the legal rights to abortion enshrined in Roe v. Wade.

Limits on the legal right to abortion are sweeping through legislatures across the United States, from moves to require women seeking abortion to undergo intrusive ultrasounds, to the defunding of Planned Parenthood, America’s largest family planning provider.

Behind the raft of bills and regulations is one group with an aggressive approach: a non-profit, anti-abortion group called Americans United for Life.

It describes itself on its website as “public-interest law and policy” group with a simple mission: “Everyone is welcomed in life and protected in law”.

In effect, it is the legal arm of the anti-abortion movement, with an orchestrated campaign to undo on a state-by-state basis the legal rights to abortion enshrined in the historic Roe v. Wade supreme court decision in 1973.

Last year was a record-breaker in terms of the number of bills restricting abortion access: according to the Guttmacher Institute, a non-profit body that seeks to advance reproductive rights, there were 92 such provisions enacted in 24 states. Almost a third of them, 28, came via AUL.

The Washington-based group drafts “model legislation” including gestational limits on abortions, additional regulation on abortion clinics, and bans on insurance cover for abortion and ultrasound requirements. In addition, it is pursuing efforts at both the federal and state level to defund Planned Parenthood.

Charmaine Yoest, president and CEO of AUL, told the Guardian that the group is currently working in 39 states and “actively consulting” with legislators in 26 of them.

Because AUL only claims “victories” over legislation it has drafted, rather than inspired, any assessment of the influence the group wields is likely to be an underestimate. “We have to be careful in claiming credit for something because sometimes it gets revised,” said Yoest, who came to the group three years ago from former Arkansas governor Mick Huckabee’s presidential campaign. “Sometimes legislators look at our legislation and then go to their legislative drafting shop.”

Every year, AUL publishes a list of its newly-drafted model legislation and a state-by-state legal guide, Defending Life. It has become a “go-to” manual for pro-life legislators. Rick Perry, the governor of Texas, former Republican presidential candidate, and pro-lifer, described the guide as “ammunition in a fight that is far from over”.

The group has a modest budget, some $3.7m last year according to public filings. But its influence is considerable and expanding: it has been involved in every legislative case involving life before the supreme court since Roe v. Wade.

“Seven years ago, when we started putting Defending Life together, we had five pieces of legislation,” said Yoest, who earns $194,337, including benefits. “Now we have 44.”

The group’s money comes from undisclosed donors. When asked who they are, Yoest replied: “People committed to pro-life help us with donations. Some of them are listed. We protect their confidentiality. We have a broad base of support and many supporters who have been with us for many years. ”

In February, the Washington Post credited Yoest as being partly responsible for decision by a prominent cancer charity, Susan G Komen for the Cure, to withdraw defunding from Planned Parenthood. AUL’s report, The Case for Investigating Planned Parenthood, sparked a Congressional investigation that was cited as the reason Komen withdrew funding for the healthcare provider. Komen eventually reversed its decision after a public outcry. At the time, Yoest described Komen’s funding withdrawal as “some of the best news of my entire life.”

Her fight against Planned Parenthood continues. AUL is behind legal action in at least seven states to defund the group, but many of them are tied up in court challenges. In Texas, for instance, a group of Planned Parenthood affiliates who do not provide abortions challenged a state ruling to exclude them from a healthcare program, saying that it would adversely affect thousands of disadvantaged women in the state who depend on it for vital cancer screenings and other services.

So far in 2012, a busy election year during which some states are not holding a legislative session, 15 pro-life, AUL-backed state resolutions have been enacted or adopted, according to preliminary AUL analysis. A full report is due out in the summer.

Among AUL’s celebrated victories are several that have attracted fierce opposition. In February, Virginia’s mandatory ultrasound bill, based in part on AUL’s model legislation, was widely criticised. Doctors said a requirement for an invasive transvaginal probe before an abortion was unnecessary in early pregnancy and represented interference of politics into healthcare. Women’s groups said it represented an effort to “shame” women into continuing with their pregnancies. The bill was amended after Democratic representatives warned it could criminalise doctors by obliging them to carry out invasive procedures that could constitute a sex crime under state law.

When asked about the criticism, Yoest laughed. “The whole first part about criminalising doctors – that was made up by the marketing department of Planned Parenthood, who want to take it into the political field because of the governor [Republican Bob McDonnell], who had been talked about as a possible vice-presidential candidate.”

Yoest insists that the legislation “protects women’s health” and that a sonogram is necessary to ensure the pregnancy is not ectopic. She cited similar legislation passed in Texas where the law was upheld by a three-judge panel at the fifth circuit court of appeal. “My reaction as a woman it is absolutely appalling for women who hold themselves up as protecteos of women’s health to be against this legislation that protects women’s health.”

The Sunlight Foundation recently compared ultrasound bills circulating in state legislatures with the AUL model legislation. It found matching text in 13 states, including Virginia.

Yoest is scathing about criticism levelled at another AUL-inspired bill discussed last year by legislators in South Dakota. The proposed bill would have altered the state’s definition of “justifiable homicide” to include the killing of an unborn child, which critics said would allow the murder of abortion doctors. It was abandoned.

“That was baloney,” said Yoest. “We had a piece of legislation that gave women the right to defend themselves and their babies. That came out of concern for battered women and was a real issue for defending women’s rights.”

This year, AUL has worked with local legislators in Georgia to help push through a bill enacting an abortion limit at or after 20 weeks’ gestation, with no exemptions for victims of rape or incest. Arizona was the first state to enact AUL’s model legislation on banning abortions after 20 weeks.

Yoest’s personal view on women made pregnant by rape or incest is this: “It doesn’t solve one tragedy to effect another.” She says “many friends” in the pro-life movement who have been victims in such cases agree. “They are the ones who are qualified to speak about this,” she said.

Yoest will not reveal her plans for the election, but said that this year, the organization will continue to promote AUL’s mission. “AUL believes that all human life should be defined from conception to natural death. There’s a host of issues in that and we are committed to our efforts as long as it takes.”