Twelve abortions were carried out in Northern Ireland last year, official statistics show.
The 1967 Abortion Act, which established legal abortion, has never applied in Northern Ireland.
Terminations are only permitted in cases where the woman's life is in danger or there is a permanent or serious risk to her mental or physical health.
Amnesty International is seeking liberalisation of the strict rules and said more than 900 women travelled to England and Wales for the procedure during the same period.
Campaign manager Grainne Teggart said, "There's a significant gap between the number of women who were allowed an abortion in Northern Ireland last year compared with the number of women who travelled to access the service."
She continued, "This demonstrates just how restrictive and unfit Northern Ireland's abortion law is."
Terminations are available on the NHS for women from Northern Ireland elsewhere in the UK.
Amnesty believes the procedure should be provided in Northern Ireland but it faces strong opposition from pro-life lobbyists and the DUP who stress the sanctity of the unborn infant's life.
Ms Teggart said, "Because of the near-total abortion ban in Northern Ireland, up to 1,000 women fly to other parts of the UK to have abortions every year.
"Countless others go online to purchase abortion pills, risking prosecution in doing so."
Stormont's Department of Health said there were 12 terminations of pregnancy in health service hospitals in Northern Ireland during 2017/18, one less than the previous year.
Eight involved women aged 30 and over and four on those aged 25-29.
They were carried out on women normally resident in Northern Ireland.
Ms Teggart asked, "How can it be the case that it's OK for women to fly to England or now get a train to the Republic of Ireland to have an abortion, but it's not OK for them to access the health service at home?
"It makes no sense. It's time the UK Government ended the hypocrisy and inequality.
She continued, "Northern Ireland has one of the cruellest abortion laws in the world, and our reproductive rights are falling further and further behind.
"The UK Government cannot ignore the grave situation for women here. Abortion must be decriminalised - made free, safe and accessible without having to travel."