It’s a fairly large number, 100,000, but nice and round. Easy to compute. Most of us could even divide it by 10, at a push. Apparently it is this convenient roundedness that led the Advertising Standards Authority (ASA) this week to dismiss complaints about recent claims on a billboard that Northern Ireland’s abortion laws have saved “100,000” lives. In its statement, the ASA said: “We considered that 100,000 was a large, round number that readers would typically associate with estimates” – and was therefore unproblematic.

Funded by a campaign called Both Lives Matter, the billboard prompted 14 complaints, but the ASA decided that its assertion was not misleading – despite the campaign admitting that it is not possible to calculate an exact figure, although its estimate is both “credible” and “conservative”.

It is not just the advertisement that is misleading and offensive, but also the very name of the campaign behind the billboard.

Describing itself as “pro-women and pro-life”, Both Lives Matter is a recent addition to the Northern Ireland anti-choice landscape, where abortion is permitted only if a woman’s life is at risk or there is a very serious risk to her mental or physical health. Fatal foetal abnormalities and pregnancies resulting from sexual crime such as rape or incest are not included.

And yet, somehow, in all its talk of “both” lives mattering during a crisis pregnancy, the campaign fails ever to mention the pregnant woman. What is happening to that person’s life – their body, their dreams, their finances, their mental health – is, for a campaign seemingly more intent on oppressing women than liberating them, nothing more than a word association game meant to draw a provocative parallel with a real struggle for civil rights.

Playing on Black Lives Matter is not just cynical, it’s offensive. A campaign started by three black women – Patrisse Cullors, Alicia Garza and Opal Tometi – to highlight the gross injustice and racial dimensions of police brutality in the US, it owes much of its strength not only to the mothers of the men and women killed by police, but to women of colour writ large, who bear the brunt of America’s institutionalised racism and sexism. The concept of reproductive rights and reproductive justice, which goes far beyond the simple right to choose whether or not to continue with a pregnancy, is integral to Black Lives Matter, because it also means the right to parent your child in a safe environment without fear – something consistently denied to black families by police and institutional injustice.

Defined by the Sister Song Women of Color Reproductive Justice Collective as “the human right to maintain personal bodily autonomy, have children, not have children, and parent the children we have in safe and sustainable communities,” reproductive justice as a concept was developed by women of colour who saw many of their communities challenged not just by an absence of accessible abortion, but by poverty, racism and discrimination.

It is often poor women of colour whose access to reproductive healthcare is most affected by anti-abortion laws in states such as Texas, where the recent HB2 law increased the distance to the nearest abortion clinic by more than 100 miles in some places. This can be an insurmountable burden for women with low incomes, often women of colour, and is a pattern being repeated across America.

Concepts such as reproductive justice and campaigns such as Black Lives Matter are a response to oppression and domination. There are parallels to be drawn with abortion access in Northern Ireland, but it is not the one that anti-abortion protesters attempt to make. Rather, it is an understanding of how human rights might be used to liberate communities, rather than excuse and justify their oppression.

The hijacking of such a powerful concept by the Both Lives Matter campaign is a cynical attempt to spin the language of human rights into froth to hide their true agenda – the subjugation of women. An appropriation of intersecting oppressions, Both Lives Matter neither cares about women’s lives, nor shares an affinity with Black Lives Matter – beyond using a powerful rallying cry for human rights as a cover to maintain the marginalisation of women in Northern Ireland.

It is perhaps beyond the remit of the ASA to name this for what it is. But it is not beyond ours.

• Elizabeth Nelson is an activist with the Belfast Feminist Network