By Kara Fox, CNN

(CNN) -- Argentina could make history on Tuesday, as its Senate votes on a bill to legalize abortion.

The procedure has long been a divisive issue in the Catholic-majority country, with the impending vote galvanizing activists on both sides of the debate.

Campaigners for abortion rights and anti-abortion protesters have organized demonstrations in front of the Palace of the Argentine National Congress in Buenos Aires where the vote will take place.

Mariela Belski, executive director of Amnesty International Argentina and an ambassador for the global women's rights movement She Decides, was preparing to travel to the Senate on Tuesday afternoon, where she will watch the debate and subsequent vote unfold inside the chamber.

Belski told CNN that if the law passes, it will "open a new era for women's rights in our country."

She added that it would enshrine "what is really happening in this country into law. Every day people in here have abortions -- and this law is saying abortion exists."

Women's reproductive rights groups are hopeful that if the bill passes in Argentina -- the third-most populous country in South America -- it could set the stage for wider reform across the region.

Tamara Taraciuk Broner, acting deputy director of Human Rights Watch (HRW) Americas Division, told CNN that if the law passes, it will "send a very strong message to the region that it is possible to move forward with legalization of abortion -- even in a Catholic country like Argentina."

Abortion in Argentina is currently only permitted when a pregnancy results from rape, or if a pregnancy endangers the life or health of the woman. In all other circumstances, abortion is illegal and is punishable by up to 15 years in jail.

Broner explained that people who currently have the right to access abortion don't really have "a real opportunity to do so because they face enormous barriers." Argentinian doctors have the option to "conscientiously object" to performing abortions, for example, if doing so would go against their religious or personal beliefs.

If the Senate votes in favor of the proposed law, abortion will be legalized in all cases up to 14 weeks.

Earlier this month, the country's lower house of Congress approved the landmark government-backed bill. The Chamber of Deputies passed the bill on December 11 with 131 votes in favor, 117 against, and six abstentions, before moving to the Senate for debate and Tuesday's decision.

Amnesty International welcomed the lower house approval and called on the country's Senate not to "turn its back" on women.

"Legal abortion is an imperative for social justice, for reproductive justice and for human rights," said Belski.

Belski said in a statement that the national debate on abortion had been positive over the last few years, as it had "succeeded in making visible the failure of the criminalization of women as a state policy."

"The Senate must now put an end to clandestine abortions. The legalization of abortion saves lives and addresses a key public health issue," she said.

Nearly 40,000 women and children in Argentina were hospitalized in 2016 as a result of unsafe, clandestine abortions or miscarriages, according to a report from HRW.

Citing National Health Ministry data, the HRW report found that 39,025 women and girls were admitted to public hospitals for health issues arising from abortions or miscarriages, with over 6,000 of them between the ages of 10 and 19.

If passed, experts say the new law will allow 13- to 16-year-olds with normal pregnancies to access abortion services without a guardian.

The bill also uses inclusive language that acknowledges that not all people who become pregnant identify as women.

Camila Fernandez, a self-identifying transgender woman, who was instrumental in the push for the bill's language that reads "people with ability to be pregnant," told CNN that the youth and the LGBTQ community were instrumental in challenging an "adult centrist and patriarchal power that has perpetuated privileges and injustices."

Argentina's current restrictions on abortion are replicated across South America.

Across Latin America and the Caribbean region, only Cuba, Uruguay, French Guiana and Guyana allow for elective abortions, according to the Center for Reproductive Rights. In Mexico City and the Mexican state of Oaxaca, abortions are also available on request, but are severely restricted throughout the rest of Mexico.

By contrast, El Salvador, the Dominican Republic, Haiti, Honduras, Nicaragua and Suriname ban abortions in nearly all circumstances. Colombia, Costa Rica, Guatemala and Panama allow for abortion only if it's to preserve the woman's health or help save her life.

'Troubling numbers'

In 2018, during the conservative administration of President Mauricio Macri, a previous attempt to legalize abortion in Argentina passed the lower house, but was narrowly defeated in the Senate.

Abortion rights advocates from a wide number of human and women's rights groups organized mass demonstrations across the country in support of that vote, donning green handkerchiefs to signify their backing -- a move that became known as the green wave.

It also saw huge support from the anti-abortion movement who dressed in blue -- the color of the "save both lives" movement, and that of the national flag.

Both groups have continued to demonstrate since, with the abortion rights movement now super-charged by the support of President Alberto Fernández, who has been in power for more than a year.

In a recorded address in November 2019, shortly before his inauguration, Fernández pledged to "put an end to the criminalization of abortion," underlining his commitment to a campaign promise.

Wearing a green tie -- a symbol of the abortion rights movement -- Fernández said that criminalizing the procedure unfairly punishes "vulnerable and poor women," adding that they were the "the greatest victims" of Argentina's legal system.

"The criminalization of abortion has been of no use," he said, noting that it "has only allowed abortions to occur clandestinely in troubling numbers."

Fernández said that more than 3,000 people had died from illegal abortions since 1983.

No official figures are available for how many illegal abortions take place in Argentina, but the National Health Ministry estimates that between 371,965 and 522,000 procedures are performed annually.

While the government has a majority in the Senate and Fernández backs the bill, the result of the vote is not a foregone conclusion.

Argentina, the birthplace of Pope Francis, has seen a gradual rise in agnosticism in recent years, although 92% of Argentinians still identify as Roman Catholic, according to the CIA.

And while a 1994 constitutional reform removed the requirement that the Argentinian president must be Catholic and guaranteed freedom of religion, the constitution also cements government support for the Catholic Church and recognizes Roman Catholicism as the official religion.

The Pope -- and other Church leaders -- have also weighed in on the debate.

In November, Pope Francis encouraged the anti-abortion group Mujeres de las Villas to "move forward" with their work, writing in a handwritten letter, addressed to congresswoman and group intermediary Victoria Morales Gorleri that "the problem of abortion is not primarily a question of religion, but of human ethics, first and foremost of any religious denomination."

"Is it fair to eliminate a human life to solve a problem? Is it fair to hire a hit man to solve a problem?" he wrote.

Anti-abortion activist and student Agostina López, 20, demonstrated on Monday and was en route to protest against the bill on Tuesday. She told CNN that the vote signified "a complete loss of values ​​such as respect for life and for women."

"Without the right to life none of the other rights make sense," López said, adding that if the law passes, it would give a "false message that the killing of innocent babies is no longer a serious (matter)."

On Saturday, the Church of Argentina called on the Senate to vote against the bill, with Bishop Oscar Ojea, president of the local bishops' conference and an outspoken opponent of abortion saying that a vote against the bill was supported by "medical science and law," Reuters reported.

If the bill is passed, doctors will still have the option to "conscientiously object" to performing abortions, however, the new law stipulates those who object to performing the procedure will have to find another doctor to do so.

On Tuesday, the Senate will also debate and vote on a complimentary bill that will strengthen the social and economic safety net for pregnant individuals facing economic hardships who want to continue their pregnancies.

If passed, the "1,000 day plan" will strengthen services from pregnancy up to the first 1,000 days of a child's life.