Pretoria News editor-in-chief Piet Rampedi said he was “full of sadness and regret” for the scoop which he said damaged Independent Media’s reputation.
Gosiame Sithole, 37, made headlines around the world following reports that she had ‘given birth to 10 babies in a hospital in Pretoria’.
Doubts, however, were raised because doctors had no record of the birth and Pretoria News had no proof that the children actually existed.
Ms Sithole has since been admitted to a psychiatric ward after being found with a relative on June 17.
The reporter said he was convinced the woman was pregnant and gave birth – but not 10 babies.
He said he wrote the article as a “wellness story” but now thinks he should have treated it as an investigative article.
Mr Rampedi wrote a letter to the editor of the group that owns his newspaper, saying: “Let me start by stating at the outset that I stand by the fact that Gosiame Sithole was pregnant and has given birth. I have no doubt and never have.
“Either way, I am sorry for the reputational damage the consequences of the story have caused to the group, the company and my colleagues in general. “
He added, “I never asked for documentary evidence of the pregnancy, like scans and clinic cards, for example, as I normally would with an investigative article. There was nothing to investigate, I thought. “
The letter continued, “To be frank, the story provided an opportunity for critics to criticize the professional integrity not only of myself, but also of my colleagues in the group.
“For that, I am extremely sorry. It was unfortunate.
“And I would like to apologize to you, my colleagues and the group. “
An official investigation has found that the claim that the South African woman had given birth to 10 babies earlier this month was false.
A provincial government statement said that no hospital in Guateng Province had recorded tenfold births.
Medical tests also showed Ms Sithole had not been pregnant recently, BBC News reports.
A reason behind the making of the story has not been given.
The woman is now being held under the Mental Health Act for observation and will be supported.