The terms of reference have been published for the Health Information and Quality Authority investigation into the safety and standards of maternity care at the Midland Regional Hospital in Portlaoise.

The inquiry was sought by Minister for Health James Reilly after the deaths of a number of babies at the hospital's maternity unit over a six-year period.

The deaths were highlighted in a RTÉ Investigations Unit programme in January.

The HIQA investigation will assess the culture of patient safety, and local, regional and national governance by the Health Service Executive.

It will also examine communication with patients and families in response to incidents.

Speaking on RTÉ's News at One Roisin Molloy, whose son Mark died following birth at the hospital in 2012, described the terms of reference as "comprehensive".

She said she was especially happy that HIQA would look at national health and safety issues within the HSE, and not just at Portlaoise.

Ms Molloy said a number of issues had already been identified through the HSE's own investigation.

Last month, the hospital's clinical director, John Connaughton, apologised to the parents of babies who died.

The apology came after a report by Chief Medical Officer Dr Tony Holohan found they were treated with limited respect and consideration, and that information was withheld for no justifiable reason.