Tensions over a growing movement to ban abortion after a fetal heartbeat can be detected intensified this week as lawmakers in Georgia passed a bill that stands to become one of the most restrictive abortion laws in the country.
The bill, which narrowly passed in the Republican-controlled legislature on Friday, is expected to be signed into law by Gov. Brian Kemp, a Republican. The measure generally prohibits the procedure after doctors can discern a fetal heartbeat, a milestone that happens around six weeks of pregnancy — before some women know they are pregnant.
Georgia’s so-called fetal heartbeat bill passed as momentum for similar proposals is building in several Republican-controlled state capitals. The governors in Mississippi and Kentucky signed fetal heartbeat measures into law in recent weeks, and other states — including Florida, Missouri, Ohio, Tennessee and Texas — are expected to approve similar measures this year.
But the efforts have so far not gained traction in the courts, which quickly halted the fetal heartbeat bill from taking effect in Kentuckyand found similar measures in Iowa and North Dakotaunconstitutional.
The measures clash with Supreme Court decisions that have recognized a woman’s right to an abortion until a fetus is viable outside the womb, usually around 24 weeks into a pregnancy.
Abortion opponents have said that is part of the intent: to land a new case before the Supreme Court, which became more conservative with the appointment of Justice Brett M. Kavanaugh last year, lending urgency to the question of whether Roe v. Wade, the landmark 1973 ruling that made abortion legal nationwide, could be overturned or weakened.
Those tensions were on display in Georgia, where last year’s tight race for governor showed how politically divided the traditionally red state has become and where women’s health care is a key issue. The state has faced a shortage of obstetricians and has one of the highest maternal death rates in the country.
At the State Capitol this month, anti-abortion activists were joined by protesters opposing the bill, including some dressed as characters from “The Handmaid’s Tale,” wearing the red robes and white bonnets that have become a symbol for women’s rights.
On the eve of the vote, about 50 Hollywood actors, including Alyssa Milano, Amy Schumer and Ben Stiller, wrote an open letter threatening to pull business out of the state, which is a hub for filming movies and television shows.
“We want to continue to support the wonderful people, businesses and communities we have come to love in the Peach State,” according to the letter, which was dated Thursday and addressed to the governor and the speaker of the House of Representatives. “But we will not do so silently, and we will do everything in our power to move our industry to a safer state for women if H.B. 481 becomes law.”
The American Civil Liberties Union also promised to go to court if the bill becomes law.
“For 50 years the Supreme Court has said that banning abortions before the point of viability is unconstitutional,” Sean J. Young, the legal director of the A.C.L.U. of Georgia, said on Saturday. “Every judge that has heard a challenge to such abortion bans has struck them down.”
A spokesman for Mr. Kemp could not be reached on Saturday. The governor campaigned on a promise to sign tough abortion laws and said he welcomed the chance to “fight for life at the Capitol and in the courtroom.” On Friday, he praised lawmakers for their leadership and courage.
“We stand up for the innocent and speak for those who cannot speak for themselves,” he said on Twitter. “The legislature’s bold action reaffirms our priorities and who we are as a state.”
The bill would effectively change the limit on abortion in Georgia to six weeks from 20 weeks. The measure allows exceptions to prevent death or serious harm to the woman, in cases in which the pregnancy is “medically futile” because the fetus would not be able to live after birth, and in cases of rape or incest in which a police report has been filed.
Genevieve Wilson, a spokeswoman for Georgia Right to Life, said the group supported the measure until exceptions were added.
“While H.B. 481 contains some strong personhood components, such as declaring babies in the womb natural persons, we are very saddened that it also denies equal justice and equal protection for subclasses of children in the womb,” she said on Saturday.
On Friday, tensions flashed at the State Capitol as the bill, which needed 91 votes to pass, was approved 92 to 78. As a crowd gathered in the hallway, activists shouted, “Shame!”
Erica Thomas, a Democratic state representative who is pregnant with her second child, threatened to stand outside the governor’s office in protest of his signing the bill.
Ms. Thomas said on Saturday that she hoped the bill would be struck down by the courts but she lamented that the measure had gone forward “doing nothing but to divide us.”
“I hate that we have to get to the point where we are at the will of the courts,” she said. “I wish we would be at the will of the people.”