The new law, which took effect on July 1, has threatened to close the state's last abortion clinic and make Mississippi the only U.S. state without such a facility.

Abortion rights advocates say it is a thinly veiled attempt to ban the procedure in Mississippi. Supporters of the measure argue it is necessary to ensure women's safety.

Representatives for the abortion clinic, Jackson Women's Health Organization, asked U.S. District Judge Daniel P. Jordan III to issue a preliminary injunction to prevent the state from enforcing the law while its constitutionality is being challenged.

Jordan did not rule on that request at a packed court hearing in Jackson, Mississippi, on Wednesday.

The judge instead extended the restraining order he issued on July 1 and said he would review the state Board of Health's new rules dictating how it would carry out the law at the center of the dispute.

The extension of the restraining order means the clinic can continue providing abortions for now.

Jordan said the temporary order would be in effect until he decides whether to grant the preliminary injunction. He did not indicate when that might be.

The law, signed by Republican Governor Phil Bryant in April, requires physicians who perform abortions to be board-certified in obstetrics and gynecology, and to have admitting privileges at a nearby hospital.

Doctors at the Jackson Women's Health Organization already are certified OB-GYNs, but they haven't yet been able to obtain hospital privileges.

"The issue for today is whether or not there is irreparable harm to your clients right now, and that harm could change with the facts," Jordan said at the hearing. "Today it could be the chilling effect. Three months from now it could be, 'We didn't get admitted, therefore we have to close.'"

IMPEDE WOMEN'S ACCESS?

If Jordan eventually allows the state to begin enforcing the law, the clinic will be given some time to comply before facing license revocation. The judge said it was not clear exactly how much time the state would provide.

The facility would then be allowed to stay open while it appealed any such revocation, a process that takes at least 60 days.

Clinic spokeswoman Betty Thompson has said local hospitals - some of which are religiously affiliated - face tremendous pressure in the socially conservative state not to grant privileges to doctors who perform abortions.

The Jackson Women's Health Organization argued in court documents that the law "is motivated by a desire to close down the clinic and end abortion in the state, in defiance of the Constitution and with a disregard for the rights of individuals."

"The purpose and effect is to impede women's access to abortion," said Michelle Movahed, staff attorney with the New York-based Center for Reproductive Rights, which is representing the clinic in the case.

The state said the measure reflects Mississippi's legal responsibility to protect women's health by ensuring doctors have the credentials necessary to perform the procedures and access to hospitals in case of complications.

"Protecting maternal health is a legitimate state interest," said Benjamin Bryant, special assistant to Mississippi's attorney general.

The state also said it had "substantial reason for concern" about the health and safety record of the Jackson clinic, noting that another abortion clinic run by owner Diane Derzis had its license revoked by Alabama health officials in April after "multiple and serious violations."

The Jackson Women's Health Organization said it was found to be in compliance with all applicable Mississippi laws after its most recent inspection in June, according to court documents.

Some anti-abortion state lawmakers who pushed for the measure have said they hoped it would end abortions in Mississippi. Jordan said he was trying to decide whether those statements were relevant to the decision at hand.

Mississippi, which had as many as 14 abortion providers in the early 1980s, already has some of the country's strictest abortion laws and one of the lowest abortion rates. It also has the highest teen pregnancy rate in the United States - more than 60 percent above the national average in 2010.

Thirty-nine other states say that only OB-GYNs can perform abortions, and nine others mandate hospital privileges, according to the Guttmacher Institute, a nonprofit organization focusing on sexual and reproductive rights.

The Jackson Women's Health Organization opened in Mississippi in 1996. Thompson said about 2,000 women received abortions at the clinic between July 1, 2010 and June 30, 2011.

(Editing by Colleen Jenkins and Xavier Briand)

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