The No side in the abortion referendum says graphic images targeting maternity hospitals are wrong and unhelpful.
The billboards have been displayed outside the Rotunda, Coombe and Holles Street Hospitals in Dublin in recent days.
The posters claim to a show 10-week-old foetus moments before an abortion and have sparked an angry response with some claiming the campaign has reached a new low.
However, Save the 8th spokesperson John McGuirk says it has nothing to do with them.
He said: "Those people who are doing that should stop doing it. It is wrong, it is not helpful.
"They are not affiliated with our campaign. They are not affiliated with the other major pro-life campaigns.
"These are people who in many cases are not Irish."
- Digital Desk