A day before a controversial abortion ban was set to take effect in Missouri — the law would ban abortions before many women know they are pregnant, with no exceptions for rape or incest — a federal judge put a block on it to allow pending legal challenges against it to proceed.

“The various sections specifying prohibitions on abortions at various weeks prior to viability cannot be allowed to go into effect on August 28, as scheduled,” U.S. District Court Judge Howard Sachs wrote in an 11-page opinion, CNN reported.

“However formulated, the legislation on its face conflicts with the Supreme Court ruling that neither legislative or judicial limits on abortion can be measured by specified weeks or development of a fetus; instead, ‘viability’ is the sole test for a State’s authority to prohibit abortions where there is no maternal health issue,” Sachs wrote.

Missouri has became a flash point among other conservative states that sought to challenge the Supreme Court’s 1973 Roe v. Wade ruling that established a woman’s right nationwide to an abortion. Those states’ efforts triggered a wave of lawsuits from abortion rights advocacy groups.

Planned Parenthood and the American Civil Liberties Union of Missouri filed a suit against the state, saying the law was unconstitutional and contrary to the Roe v. Wade decision.

The Missouri law signed in May is one of the harshest in the country. If the court doesn’t uphold the ban, the bill includes less-strict bans ranging from 14 weeks to 20 weeks, the Associated Press reported.

“We are in the fight of our lives to protect abortion for 1.1 million Missouri women of reproductive age in our state,” Colleen McNicholas, chief medical officer of Planned Parenthood of the St. Louis Region, said last month. “The attacks are relentless, but our commitment to our patients’ rights and freedoms is unwavering.”

While conservatives championed the ban, with Missouri House Speaker Elijah Haahr (R) saying the bill “stood for the unborn,” opponents said it would only drive women to get unsafe procedures out of state or seek unsafe operations on their own.

“We will be killing women with this bill,” Rep. Sarah Unsicker, a Democrat from the St. Louis suburbs, said before the vote.

Gov. Mike Parson (R) made a forceful statement with the bill passage, vowing to make Missouri “one of the strongest pro-life states in the country.”

Lindsey Bever contributed to this report.

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