Protesters fill the Iowa State Capitol rotunda, as the Iowa Legislature convened for a special session to pass a six-week ‘fetal heartbeat’ abortion ban on Tuesday. The bill was challenged in court on Wednesday. Zach Boyden-Holmes/The Des Moines Register via Associated Press

DES MOINES, Iowa — Iowa’s new ban on most abortions after roughly six weeks of pregnancy was challenged in court on Wednesday, launching what will likely be a lengthy and emotional legal battle just hours after the Legislature approved it in a late-night vote.

Republican Gov. Kim Reynolds says she’ll sign the bill into law on Friday. It would take effect immediately.

The bill was passed with exclusively Republican support in a rare, one-day legislative session lasting more than 14 hours. There were vocal – and sometimes tense – objections from Democratic lawmakers and abortion advocates protesting at the Capitol.

The challenge, brought by the ACLU of Iowa, Planned Parenthood North Central States and the Emma Goldman Clinic, requests that a district court temporarily put the soon-to-be law on hold as the courts assess its constitutionality. A hearing is scheduled for Friday afternoon, according to court documents, just before the governor’s bill signing.

Abortion is currently legal in Iowa up to 20 weeks of pregnancy, but that would change with the stroke of Reynolds’ pen Friday. The new legislation prohibits almost all abortions once cardiac activity can be detected, which is usually around six weeks of pregnancy and before many women know they are pregnant.

Reynolds ordered the special session after Iowa’s Supreme Court declined in June to reinstate a practically identical law that she signed in 2018. She called the new bill a vindication of her earlier efforts.

“The Iowa Supreme Court questioned whether this legislature would pass the same law they did in 2018, and today they have a clear answer,” Reynolds said in a statement. “Justice for the unborn should not be delayed.”

There are limited circumstances under the measure that would allow for abortion after the point in a pregnancy where cardiac activity is detected: rape, if reported to law enforcement or a health provider within 45 days; incest, if reported within 145 days; if the fetus has a fetal abnormality “incompatible with life”; or if the pregnancy is endangering the life of the pregnant woman.

Planned Parenthood North Central States said Wednesday they are preparing to have to refer patients to other states if the law isn’t blocked. As of Wednesday, 200 patients were scheduled for abortions at Iowa Planned Parenthood or the Emma Goldman Clinic this week and next, according to the court filings. Most of them past the six-week mark in their pregnancies.

“We are seeking to block the ban because we know that every day this law is in effect, Iowans will face life-threatening barriers to getting desperately needed medical care – just as we have seen in other states with similar bans,” Rita Bettis Austen, legal director for the ACLU of Iowa, said in a statement.

Most Republican-led states have drastically limited abortion access in the year since the U.S. Supreme Court overturned Roe v. Wade and handed authority on abortion law to the states. More than a dozen states have bans with limited exceptions and one state, Georgia, bans abortion after cardiac activity is detected. Several other states have similar restrictions that are on hold pending court rulings.

A district court in Iowa found the state’s 2018 abortion ban unconstitutional in 2019, which at the time was based on rulings by the U.S. Supreme Court and Iowa’s Supreme Court that had affirmed a woman’s fundamental constitutional right to abortion.

After both bodies overturned those rulings last year, the governor sought to reinstate the 2018 law. But the state’s high court deadlocked last month without ruling on the merits of an abortion ban, leaving that law permanently blocked and leaving open the question of how the courts would rule on a new one.