If the "yes" forces seeking a constitutional change prevail as the polls suggest, Ireland's parliament will be charged with coming up with new abortion laws.
The Irish government's push to liberalise the laws is in contrast to the United States, where abortion has always been legal, but President Donald Trump backs stripping federal funding from women's health care clinics that offer abortions.
People arriving at polling stations on Friday in more traditional rural areas and city centres spoke about the momentousness of a morally complex decision.
In media interviews in the following weeks, Praveen Halappanavar said he and his wife had repeatedly asked for the pregnancy to be terminated after her admission to hospital, but they had been told: "This is a Catholic country".
In what was traditionally one of the most religious countries in Europe, the Church's influence has waned in recent years following a series of child sex abuse scandals. Despite Ireland's move toward secularism and approval of redefining marriage, polls on how the Eighth Amendment vote would go were extremely close toward the end of the abortion vote.
"I took it really personally, this vote, and said I'm going to come out today and vote for what I believe in".
"It's women's rights, I feel it's basic healthcare, human rights that women deserve, and we're not getting that".
Ireland held a referendum on the Eighth Amendment of the country's constitution on May 25, 2018 that bans abortion and if this is repealed, the Irish government could legislate terminations.
Counting began at 9am local time but an official result is not expected until Saturday evening.
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With the likes of Dimitri Payet and Florian Thauvin shining in attack, Marseille have impressed throughout the campaign. Payet had rolled the ball through to Valere Germain in the opening five minutes only for the midfielder to fire wide.
The country's leaders supported a "yes", an outcome that would repeal a 1983 constitutional amendment requiring authorities to treat a fetus and its mother as equals under the law.
"I've been awake all night".
Speaking to the Guardian by phone from his home in Karnataka, south-west India, Andanappa Yalagi said: "We've got justice for Savita, and what happened to her will not happen to any other family now. Hopefully our day has come".
And the man who had the exact same thought and pretty much set the entirety of Twitter off.
Canvassers were out on the city's streets holding up signs and wearing t-shirts with campaign slogans. This means that some politicians want substantial legislative restrictions on abortion.
But across the city, Finbar O'Regan, 50, said he wanted a "good, strong No vote".
Abortion was illegal in Ireland under the Offences against the Person Act of 1861, but when contraception was legalised in 1974, there was concern from many conservatives that abortions would follow. It would also likely end the need for thousands of Irish women to travel overseas - mostly to neighboring Britain - for abortions they can't get at home.
"For decades, Irish women have been forced to travel hundreds of miles to our clinics in England, often alone, at a huge personal and emotional cost".
The proposed legislation - which may be introduced next week - is expected to be abortion on demand during the first 12 weeks of pregnancy for healthy babies and later throughout pregnancy for nebulous "health" reasons, for babies with disabilities, and babies conceived in rape.