The measure, which state lawmakers gave a final nod to on Tuesday, would bar healthcare professionals from performing abortions after 20 weeks of pregnancy, except in the case of a medical emergency. Only a small number of these abortions are performed in the state.

"This legislation is consistent with my strong track record of supporting common sense measures to protect the health of women and safeguard our most vulnerable population - the unborn," Brewer said in a statement.

"Knowing that abortions become riskier the later they are performed in pregnancy, it only makes sense to prohibit these procedures past 20 weeks," she added.

With Brewer's signature, Arizona joins six other states that have put similar late-term abortion bans in place in the past two years based on hotly debated medical research suggesting that a fetus feels pain starting at 20 weeks of gestation.

Georgia lawmakers approved a similar bill in March that now awaits the signature of Republican Governor Nathan Deal.

Cathi Herrod, president of the conservative Center for Arizona Policy, said the passage of the law, was a "momentous victory for pro-life advocates."

"Abortion not only ends the life of a preborn child, but it also seriously endangers the health and safety of women," she said.

'EXTREME ASSAULT ON REPRODUCTIVE RIGHTS'

Opponents of Arizona's new law, which will take effect this summer, said it set a "dangerous new standard for hostility to women, doctors and reproductive rights."

"To call this an extreme assault on reproductive rights would be a massive understatement. In its cruelty and its callous disregard for women's lives, it is downright appalling," said Nancy Northup, president of the Center for Reproductive Rights.

The U.S. Supreme Court legalized abortions nationwide in 1973 but allowed states to ban the procedure after the time when the fetus could potentially survive outside the womb, except where a woman's health was at risk.

Late-term abortions will still be allowed in Arizona in situations where continuing a pregnancy risks death or would "create serious risk of substantial and irreversible impairment of a major bodily function." This is to be determined by a physician's "good faith clinical judgment."

The law also requires a woman to have an ultrasound at least 24 hours prior to having an abortion, instead of the one hour previously mandated under state law.

State officials are also required to create a website that details such items as the risks of the procedure and shows pictures of the fetus in various stages.

Bryan Howard, president and CEO at Planned Parenthood Arizona, said the law was part of a "harmful" nationwide drive by conservatives to curb not only abortions but other services affecting women's health.

"We're seeing the hubris overreach in states across the country, not just in the regulation of abortion but in mainstream Planned Parenthood services like birth control and cancer screening," he said.

(Editing Tim Gaynor and Cynthia Johnston; desking by Cynthia Osterman and Lisa Shumaker)

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