The Health Service Executive spent almost €170,000 last year sending patients abroad for the purpose of having a sex change.
Gender reassignment or 'sex-change' surgery is not performed in Irish hospitals but it can be arranged in another country and funded by the HSE under the Treatment Abroad Scheme.
The procedure is considered a treatment for Gender Identity Disorder (GID) and involves the reconstruction of genitalia to resemble that of the opposite sex.
Last year, the HSE paid for 32 visits to hospitals outside of the State for treatments and procedures that allowed public patients to change their gender.
Four patients availed of the treatment in 2014 at a total cost of €166,543; including €4,986 for travel expenses and €161,557 for clinical services relating to the procedure.
Sex-change operations have received international media attention in recent weeks after former American Olympian Bruce Jenner - Kim Kardashian's step-dad - announced that he is to undergo the procedure.
He made the announcement in an interview with veteran TV reporter Diane Sawyer.
"I have always been very confused with my gender identity since I was this big," he said lowering his hand to a foot or two above the ground. He said that while he was born with a male body he has a "female soul".
According to the HSE, the average cost of an assessment and the associated surgery for an Irish patient being send abroad is approximately €30,200; although the cost of female-to-male operations is considerably higher than male-to-female procedures.
More than 50 public patients have now undergone sex-change surgery under the Treatment Abroad Scheme. Five patients travelled abroad for the treatment in 2013, while 12 availed of the scheme the year before.
In a statement, the HSE said that the volume of requests for transgender surgery each year would not support the provision of a specialised service in Ireland.
"Clinical decision making determines whether or not someone is put forward for this procedure under the Treatment Abroad Scheme.
"Therefore, each of the patients who availed of the treatment did so by way of clinical referral from their treating physician in Ireland, as per the guidelines.
"The Scheme allows an Irish-based consultant to refer a patient that is normally resident in Ireland for treatment, unavailable in Ireland, and a proven form of medical treatment that is not an experimental therapy."
Figures obtained under the Freedom of Information Acts reveal that the HSE and its health board predecessors paid for 49 patients to have sex-change surgery between 1999 and 2014.