Washington CNN  — 

A federal judge blocked a Mississippi law on Friday that forbids abortion after the detection of a fetal heartbeat, as early as six weeks into a pregnancy.

In issuing a preliminary injunction, Judge Carlton Reeves said the law “threatens immediate harm to women’s rights, especially considering most women do not seek abortions services until after six weeks.”

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“Allowing the law to take effect would force the clinic to stop providing most abortion care,” wrote Reeves, adding that “by banning abortions after the detection of a fetal heartbeat, the law prevents a woman’s free choice, which is central to personal dignity and autonomy.”

The law was set to take effect in July.

Supporters of abortion rights argue the law collides with Supreme Court precedent, violating a woman’s right to seek an abortion prior to viability.

The law is part of a new wave of restrictions introduced by Republican-led states – emboldened by President Donald Trump – to introduce legislation that calls into question Supreme Court precedent. The laws, none of which have gone into effect in 2019, triggered protests across the country on Tuesday, the same day Reeves heard arguments in Mississippi.

Critics worry that with the appointment of Justice Brett Kavanaugh to take the seat of swing vote retired Justice Anthony Kennedy, the Supreme Court might eventually move to cut back on its landmark opinion Roe V. Wade, if not gut the 1973 decision.

Reeves sits on the US District Court for the Southern District of Mississippi. Abortion laws similar to Mississippi’s – which critics call “six-week bans” and supporters refer to as “heartbeat laws” – have been introduced in 15 states this year and passed in four: Georgia, Kentucky, Mississippi and Ohio.

At the same time, Alabama passed a near total ban on abortion earlier this month that only allows exceptions to “avoid a serious health risk to the unborn child’s mother” for ectopic pregnancy and if the “unborn child has a lethal anomaly.” The American Civil Liberties Union and Planned Parenthood filed a lawsuit Friday against Alabama’s abortion law.

State officials defending the Mississippi law in court said it was passed to further the state’s interest in regulating the medical profession in order to promote “respect for life.”

They acknowledged Supreme Court precedent on viability but argued that once a fetal heartbeat is detected, “the chances of the fetus surviving to full term are 95%-98%”

In court papers, they said the law is meant to “prohibit procedures that destroy the life of a whole, separate, unique living human being.”

Mississippi’s Assistant Attorney General Paul Barnes told Reeves in court that while the Supreme Court hadn’t upheld a pre-viability ban, that doesn’t mean it “won’t happen” in the future.

The law was challenged by the Center for Reproductive Rights representing the Jackson Women’s Health Organization, the state’s only clinic. They said the law, like similar measures in other states, is meant to be unconstitutional so that it might trigger Supreme Court review.

“Many women don’t even know they are pregnant at six weeks, and even those who do will find it nearly impossible to obtain an abortion so quickly, especially in a state with just one clinic,” Hillary Schneller, a lawyer for the Center for Reproductive Rights, said in an interview. In court, she argued the law was in “defiance” of Supreme Court precedent and is “clearly unconstitutional.”

The Center for Reproductive Rights’ president and CEO, Nancy Northup, vowed in a statement released on Friday to challenge bans like Mississippi’s “at every turn.”

“The Constitution protects a woman’s right to make decisions over her body and her life. The district court’s decision today was a resounding affirmation of this settled law,” Northup said.