Ombudsman Emily O'Reilly has criticised the General Register Office (GRO), which administers the registration of all births, deaths, marriages and adoptions in the State.
She said complaints received by her office showed instances "where the quality of service provided was below the standard which might be expected from a public service organisation".
Recommendations aimed at improving the quality of service have been accepted by the GRO.
In a report, Ms O'Reilly highlights a number of cases "where the actions of the GRO have adversely affected individual complainants".
The report refers to the case of a mother whose daughter's surname, as entered on her birth certificate, was changed without her knowledge. A mother, who had given up her son for adoption when he was eight months old, and who, 30 years later, wished to have the birth record amended, experienced difficulties.
Also highlighted are the difficulties encountered by a mother whose son's date of birth and gender were incorrectly entered on the birth register.
A couple wishing to obtain a correct version of their marriage certificate in the Irish language faced difficulties.
The report also highlights problems encountered by individuals and couples relating to the recognition of foreign divorces in Ireland.
The report notes the General Register Office's failure to respond promptly to inquiries; an unwillingness to provide clarity or helpful information in responses; a lack of sensitivity to the needs of complainants, and a failure to learn from court decisions, where evidence, unacceptable to the GRO in recognising a divorce, had been accepted.
There was also an unwillingness to raise legislative issues for review by the Department of Health.
Ms O'Reilly says that the core function of her office is to protect individuals who avail of public services from unfair, unsound and unjust actions on the part of those entrusted with their delivery.
Ms O'Reilly adds that as a consequence of the GRO's actions, "the individuals who complained to me have experienced a great deal of stress and inconvenience, in, for example, not being able to record correct details relating to the birth of their children, having doubts cast upon the legitimacy of their marriages and not being able to marry their partners when they wished to do so".
She acknowledges the importance of the role played by the GRO in the civil registration service and that, in the vast majority of cases, the service delivery is efficient and competent. However, there were shortcomings in the service provided to those who complained to her office, she notes.
