Up to 300 survivors of symphysiotomy have unanimously rejected the Government's plan for redress.
By availing of the package, survivors would have waived their right to take legal proceedings against any party - including the State.
The payout consisted of basic compensation of €50,000 to women who underwent the procedure - in which the pelvis was broken before or during childbirth.
"We will now be writing to the Government to inform them that our members … have unanimously voted to reject the plan. We will be asking them to go back to the drawing board," said SoS Chairperson Marie O'Connor.
She said the group's national executive has "been given the strongest possible mandate by its members" to negotiate.