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Mississippi Gov. Phil Bryant is the latest governor to sign into law a bill that would ban abortions once a fetal heartbeat can be detected.

The bill, signed Thursday afternoon, would prohibit abortions as early as six weeks into pregnancy, before many women even know they’re pregnant. The only exceptions would be to prevent a woman’s death or her serious risk of impairment.

“The heartbeat has been the universal hallmark of life since man’s very beginning,” Bryant said in an address before signing the bill. “I can remember the exciting moments both with my children and grandchildren when the first sonograms were taken and that heartbeat could be heard.”

But that “celebration is often turned into tragedy when the child’s life is taken,” he continued. “We here in Mississippi believe in protecting and defending the whole life of that child. … From education to safety to healthcare, it is the child that we are fighting for here in Mississippi. And today, Senate Bill 2116 begins that at the earliest possible opportunity.”

Mississippi Gov. Phil Bryant is surrounded by lawmakers as he signs a bill that would ban most abortions once a fetal heartbeat can be detected.

Numerous states across the nation have floated similar bills; right now lawmakers in Ohio, Tennessee and Georgia are trying to pass them. But just as often as they get introduced, they get shut down. They are held up in committees, rejected in legislative votes, vetoed by governors and struck down in courts.

Not one state has managed to put a “heartbeat bill,” as they’re often referred to, into lasting practice. And yet they keep on happening.

Earlier this week, a judge stopped Kentucky’s version of the heartbeat bill from becoming law. Iowa’s law, too, was blocked in January, after a judge declared it unconstitutional.

The Center for Reproductive Rights has already promised a fight in Mississippi.

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“This ban is one of the most restrictive abortion bans signed into law, and we will take Mississippi to court to make sure it never takes effect,” Hillary Schneller, staff attorney for the legal advocacy group, said in a written statement. “A judge struck down the state’s 15-week ban just months ago, but lawmakers didn’t get the message. They are determined to rob Mississippians of the right to abortion, and they are doing it at the expense of women’s health and taxpayer money. This ban – just like the 15 week ban the Governor signed a year ago – is cruel and clearly unconstitutional.”