Dr Rhona Mahony has said that the money – which was paid on top of her salary and allowances worth €236,000 – came from professional fees from private patients.
She added that the money did not come from fundraising or charitable donations.
“My remuneration as Master is strictly in line with the contract I have with the National Maternity Hospital and is exactly in compliance with public service pay requirements for my position,” she said.
“As a Consultant Obstetrician my contract allows me to provide clinical care to private patients, as is the case with all Consultants in the Irish health service who have the same Consultant contract as myself. The provision of private patient care is fundamental to the health service as currently structured.
“The €45,000 paid to me, and labelled by the media as a ‘top-up’, is in respect of professional fees from private patients attending the National Maternity Hospital.
“With regard to this, I have the same contractual terms as all other medical Consultants in the Irish health service who have the same contract. The existence of this income has been reported to the HSE in May 2012 as part of a routine confidential internal audit carried out by the HSE. To be absolutely clear, I have never received any additional remuneration from the health service or any other source, including fundraising and charitable donations.
“I have been personally vilified over the last few days. This has been utterly unwarranted.”
The statement comes as a number of hospitals have stonewalled calls from the state's health chiefs to confirm whether they comply with public pay scale policies.
Taoiseach Enda Kenny revealed those who refused to share information on whether they have breached salary caps with the Health Service Executive (HSE) will be hauled before Government to explain.
"Let me assure you that a report is now being prepared to be presented to the minister for health and that those hospitals that did not respond are now going to be called in to account for their failure to respond," Mr Kenny said.
The country's 44 hospitals and health agencies had until Tuesday night to provide the HSE with information on wages after it emerged that a senior manager at Tallaght Hospital was paid an additional 150,000 euro in payments since 2005.
Mr Kenny said the Government is determined to sort out the issue of unauthorised payments and that Health Minister James Reilly is due to receive a report from the HSE.
"That report will be published on the departmental website, discussed in the Dail and the Government will take action to see that where unauthorised and unapproved non-exchequer top-ups were given that were clearly in breach of public pay policy will end," he said.
At the same time as Dr Mahony issued her statement, the National Maternity Hospital also released a statement.
“No payments are made to NMH personnel from any funds raised or received as donations to the NMH or the NMH Foundation. The Board confirms that all funds so raised go directly to purchase necessary medical equipment, not provided for by allocated state funding, in order to maintain safe standards for the 9,000 babies born annually at NMH,” it said.
The Board of the NMH acknowledges the need for Dr. Mahony to issue a personal statement today in view of the unfounded and unwarranted personal attacks in the media in recent days. The Board fully endorses her statement.”