Mamamia says it was "regrettable" that an article about post-abortion syndrome (PAS), a condition that is oft-cited by anti-choice groups but discredited by medical organisations, was published on the Australian opinion and lifestyle website.
"It is regrettable that this story was published," Mamamia's head of content Holly Wainwright said in a statement to BuzzFeed News.
"The piece was not native content, it was a contributed submission."
The article, anonymously authored by "Mollusc Media", was deleted on Tuesday after BuzzFeed News put questions to Mamamia.
Wainwright did not reveal the identity of the contributor but said the organisation was "still looking into Mollusc Media".
Wainwright also failed to answer questions about whether the writer was paid for the submission and what the website's policy was in allowing contributors to remain anonymous.
"We are a human organisation and mistakes are sometimes made," she said.
"We have permanently removed the piece and we are reviewing our internal processes to ensure going forward we strengthen our checks and balances to avoid a similar error in future.
"Mamamia has and always will be a staunch pro-choice advocate."
PAS was coined by United States anti-abortion campaigner Dr Vincent Rue. It is not recognised as a diagnosis in the Diagnostic and Statistical Manual of the American Psychiatric Association.
The article, which was published on Saturday and deleted on Monday, claimed "psychologists and mental health providers are extremely divided on the issue", but failed to interview a single psychologist or mental health provider.
The article quoted Julie Cook, national director of "Abortion Grief Australia", and directed people to the organisation's website, which has no affiliation with any medical organisation, but offers resources on how a woman might seek forgiveness from God for terminating her pregnancy.
Cook is quoted in the article: "Abortion trauma has historic parallels to child sexual abuse and post traumatic stress disorder suffered by war veterans."
In 1989, the American Psychological Association (APA) concluded that legal abortion of an unwanted pregnancy did "not pose a psychological hazard for most women".
In 2008 it reached a similar conclusion in an exhaustive review from which it created this 107-page document.
Based on a comprehensive review and evaluation of the empirical literature published in peer-reviewed journals since 1989, the APA concluded: "The most methodologically sound research indicates that among women who have a single, legal, first-trimester abortion of an unplanned pregnancy for non-therapeutic reasons, the relative risks of mental health problems are no greater than the risks among women who deliver an unplanned pregnancy."
A recent study published in The Journal of the American Medical Association found that denying a woman access to abortion services has more of an impact on her mental health than the procedure itself.
You can read more about the various studies on abortion and mental health here.