THE Master of the National Maternity Hospital has said that a €45,000 salary top-up she received from the hospital was for private work.
Dr Rhona Mahony also claimed she had been vilified since the revelations emerged.
She said in a statement that the top-up was strictly in line with her contract.
And she added that she owed it to herself, her family, her colleagues and donors to the hospital to clarify her position.
The doctor, who has a taxpayer-funded salary and master's allowance of €236,000, said: "As a consultant obstetrician, my contract allows me to provide clinical care to private patients.The provision of private patient care is fundamental to the health service as currently structured."
Dr Mahony said the existence of this income was reported to the HSE in May 2012 as part of a routine confidential internal audit carried out by the body.
"To be absolutely clear, I have never received any additional remuneration from the health service or any other source, including fundraising and charitable donations," she added.
"I have been personally vilified over the last few days. This has been utterly unwarranted."
The HSE called the top-up a "privately funded allowance".
But a spokesman would not comment when asked by the Herald whether the €45,000 addition was a set yearly payment received by the doctor, or whether it was based on the number of private patients she treated.
He similarly declined to comment when asked why the top-up payment had come from a separate private account, and when he was asked how many private patients Dr Mahony treated.
"She has nothing to add to the statement," he said.