PIERRE, S.D. -- Women who want an abortion in South Dakota will face the longest waiting period in the nation -- three days -- and have to undergo counseling at pregnancy help centers that discourage abortions under a measure signed into law Tuesday by Gov. Dennis Daugaard.

Within minutes of Daugaard's announcement that he had signed the measure, anti-abortion groups said they plan to file a lawsuit challenging the measure, which one said could create particular hardships for women who live in rural areas hundreds of miles from the state's only abortion clinic in Sioux Falls.

Daugaard, who gave no interviews after signing the bill, said in a written statement that he had conferred with state attorneys who will defend the law in court and a sponsor who has pledged to raise private money to finance the state's court fight. Officials have said estimated the cost of defending the law at $1.7 million to $4.5 million.

"I think everyone agrees with the goal of reducing abortion by encouraging consideration of other alternatives," the Republican governor said the statement. "I hope that women who are considering an abortion will use this three-day period to make good choices."

Longest waiting period

About half the states, including South Dakota, now have 24-hour waiting periods, but the state's new law is the first of its kind in having a three-day waiting period and requiring women to seek counseling at pregnancy help centers, said Elizabeth Nash of the Guttmacher Institute, a research organization that supports abortion rights.

The law will certainly make it harder for some women to get abortions, said Kathi Di Nicola, a spokeswoman for Planned Parenthood Minnesota, North Dakota and South Dakota, which runs the clinic in Sioux Falls. Women could have to drive there several times to schedule an abortion, visit a crisis pregnancy center and then get an abortion, she said.

"It would most certainly be a barrier to women who have to travel. South Dakota is a rural state," Di Nicola said. "Many women who are seeking abortion care already have to take time off work, arrange for child care."

Planned Parenthood and the American Civil Liberties Union of South Dakota said they will ask a judge to strike down the measure as unconstitutional.

Supporters of the measure say the Planned Parenthood clinic gives women little information or counseling before they have abortions done by doctors flown in from out of state and the bill will help make sure women are not being coerced into abortions by boyfriends or relatives.

"Women need to just be reminded of the fact there is a natural, legal relationship between them and their child," said Rep. Roger Hunt, R-Brandon, main sponsor of the law.

The law, which takes effect July 1, says an abortion can only be scheduled by a doctor who has personally met with a woman and determined she is voluntarily seeking an abortion. The procedure can't be done until at least 72 hours after that first consultation.

Before getting an abortion, a woman also will have to consult with a pregnancy help center to get information about services available to help her give birth and keep a child. The state will publish a list of pregnancy help centers, all of which seek to persuade women to give birth.

Leslie Unruh, founder of the Alpha Center, a pregnancy help center in Sioux Falls, said many women have said they would never have had abortions if they had first received counseling at such a center.

"If we truly want to have less abortions, let's give these women the 72 hours they need to make this decision on their own without being coerced," Unruh said.

Jan Nicolay, co-chair of the South Dakota Campaign for Healthy Families, which has opposed restrictions on abortion, said the measure would invade women's privacy by forcing them to go to crisis pregnancy centers that are sham clinics set up to dissuade women from getting abortions. The law could violate federal requirements that protect the privacy of medical records, and it assumes that women cannot make decisions about abortions after talking with their families and pastors, she said.

"Now, despite the fact that South Dakotans have repeatedly spoken on issues of government interference in private decisions, we will once more be pulled into a protracted legal battle that will potentially cost the state millions in tax dollars," Nicolay said in a written statement.

Hunt said the state would only have to pay legal costs if it lost the lawsuit, and the money would be well spent to try to prevent the 800 or so abortions done each year in South Dakota. But, he said, donations are already coming into to defend the law. Some people have pledged large sums, while others are giving $25 or $50, he said.

"They want to put their money where their mouth is in the sense of protecting unborn children," Hunt said.

The South Dakota Legislature has passed several other measures restricting abortions in the past decade.

Voters rejected statewide ballot measures in 2006 and 2008 that would have banned most abortions in the state. Those measures sought to provoke a court challenge to the U.S. Supreme Court's 1973 Roe v. Wade ruling that legalized abortion in the United States.

A 2005 law requiring that women be told that an abortion will end the life of a human being has yet to be fully implemented because it remains tied up in a court fight.