MINNEAPOLIS (Reuters) - A federal judge on Thursday blocked a new South Dakota abortion law requiring the longest waiting period in the nation at 72-hours and a meeting at an anti-abortion counseling center before a woman can have the procedure.

The law, signed by Republican Governor Dennis Daugaard, also requires a doctor to certify that the pregnant woman has not been coerced into having an abortion and that the potential complications of an abortion have been explained. The law was due to take effect on Friday.

Planned Parenthood, which operates the only center that performs abortions in South Dakota, sued to block the law and U.S. District Court Chief Judge Karen Schreier granted a preliminary injunction on Thursday.

The new law is one of many abortion curbs pushed by conservative lawmakers in dozens of states this year. Other proposals included bans on late-term abortions and requirements that providers offer women sonograms of their fetuses.

(Reporting by David Bailey; Editing by Greg McCune)