When Preterm opened for abortions in 1974, its first opponents were illegal abortionists who were concerned that the clinic was stealing their business.
It withstood intimidation from standover men, political attacks and doorstep protests by religious groups for four decades until closing its doors last month, overwhelmed by financial pressures.
A late public campaign to save the clinic after it closed its doors in mid-August failed when it was sold to a private investor on Tuesday.
Save Preterm co-ordinator Claire Pullen said there were now fewer places for women to access safe reproductive healthcare.
"A lot of people held it very dear to their heart and had a lot of stories about their experiences, their sisters' experiences, their daughters' experiences at Preterm and spoke in really glowing terms about the support they got from staff and to know that it was safe for them to be there."
The not-for-profit centre began performing abortions when the only options for women who wanted to terminate their pregnancies were backyard abortions or expensive practitioners.
Supported and bankrolled by media magnate Clyde Packer, Australia Party founder Gordon Barton and barrister Geoffrey Keighley, it became the first legal abortion clinic to operate in NSW, and was until recently the only clinic exclusively offering termination services to be licensed by the NSW Department of Health and accredited under national safety standards.
But it is understood the costs of maintaining accreditation - including extra nurses and recovery beds - made it difficult for the centre to compete against new players in the market, and the board opted to close rather than lower standards.
Board members declined to comment and instructed their staff not to speak to the media.
But Helpers of God's Precious Infants co-ordinator Paul Hanrahan, who frequently held vigils outside the clinic to persuade women to change their minds, claimed victory on his Facebook page: "Who says prayer at the place doesn't work."
"It's symbolic because Preterm is the oldest in NSW," he told Fairfax Media.
"But that doesn't mean it's a victory in any way over the whole culture that allows abortion in the first place, that drives women to abortion clinics, who don't want to be there."
Dorothy Nolan, the first clinical director, recalled in 1984 that illegal abortionists who were concerned Preterm was only charging $50 for an abortion used to make threatening calls to her at home, and occasionally sent "pairs of burly men in plain clothes" to the clinic.
The clinic burnt down a year after it opened and there were suspicions that the fire was started by its political opponents, though this was never established by the police.
"There we were, a forlorn, stunned little bunch on the pavement," Nolan wrote in the 10-year anniversary newsletter.
"I remember … my angrily declaring that we would start again, though my heart was kilometres below my boots."
By 1981, anti-abortionists had become better organised, and demonstrated against the clinic by throwing bricks through the window and red paint at the front wall.
But public opinion turned, and the protesters who patrol the doors each Lent were this year matched by pro-choice campaigners, who held up placards ridiculing their opponents.
"We are the granddaughters of the witches they didn't burn," read one.
Another pointed to the religious group with a red arrow. "Preying group", it said.
Correction: An earlier version of this story incorrectly referred to Dorothy Nolan as "the late Dorothy Nolan".
