For a country so closely entwined with the Catholic Church, months of polarizing protests have signaled a seismic cultural shift. Voters will select "yes" or "no" to repeal Ireland's 8th amendment which bans all abortions except when a mother's life is at risk.
The law was created in 1983, supported by those who feared Ireland having its own Roe v. Wade moment. Since the 1973 ruling legalized abortion in America, Ireland has been considered a pro-life beacon.
It's a torch Sinead McBreen wants to carry for unborn children with disabilities. Her 3-year-old daughter Grace has Down syndrome.
"It wasn't my right to terminate, to decide when to terminate her life," McBreen said.
But pro-choice campaigners like Ivana Bacik say the current law ultimately hurts women.
"It has caused this immense trauma. It has blocked any reform of abortion law and of course it hasn't stopped Irish women having abortions," Bacik said.
In 2016, over 3,000 women from Ireland traveled to the U.K. to have abortions. That's almost nine per day. It is estimated that 1,500 illegal abortion pills are ordered online each year.
The Catholic Church in Ireland has encouraged its followers to vote "no" to abortion, but critics here say its moral authority has weakened after a series of child abuse scandals.
In the past few decades Ireland has leaned more liberal, legalizing divorce in 1995 and gay marriage in 2015.
If abortion is legalized, women will be allowed to terminate in the first 12 weeks of pregnancy.
The vote is expected to be very close.