The device had been inserted during an abortion procedure three years earlier, when the doctor at the Epsom Day Unit wrongly assumed she wanted the contraceptive.
She told the Health and Disability Commissioner Anthony Hill she suffered stress and disappointment with each passing month of failing to get pregnant, as well as facing extra costs of tests and doctor visits.
But the ADHB responded by saying she suffered only a "brief inconvenience".
The health board said there was no suggestion that the clinical treatment provided was of concern, but the failure was to obtain consent "in one case amongst thousands of similar cases".
It said the woman "suffered no physical injury or permanent harm".
A theatre nurse told Mr Hill she knew of two other similar cases where the contraceptive had been incorrectly planted.
"[The nurse] recalls that staff were advised during training that a patient (not Ms A) had had an IUCD inserted without consent.
"In addition, she recalls another incident where, after the insertion of an IUCD, she noticed that the patient concerned was on the pill."
After she expressed concern, the error was found and the patient's IUCD was removed, Mr Hill said.
The ADHB told Mr Hill it did not keep records of incidents where IUCDs were inserted in error.
But it did note that in a previous case referred to it by the commissioner, that patient had had an IUCD inserted without her consent.
"In that case, ADHB apologised to the woman and she subsequently withdrew her complaint."
The Auckland Women's Health Council, which advocates for women's health issues, described the commissioner's revelations as chilling.
"The systems at the Epsom Day Unit seemed to be acting like a conveyor belt, like a factory pushing through process with very little time to check what was going on with the women," said co-ordinator Lynda Williams.
The incident had been a "huge breach" of the rights of the woman involved, she said. "It is not okay for any procedure to be done without informed consent."
Ms Williams supported changes the unit had made as a result of the incident, including the requirement to have written consent for an IUCD to be inserted.
Fertility expert Dr Richard Fisher of Fertility Associates said it was stressful when women and couples trying to conceive were unable to.
"If you are less than 30 and you're not pregnant in six months then there's likely to be an issue because you should have conceived that quickly," he said.
"Women who are between 30 and 36 - it might well take longer than that by chance alone because the chance of conception each month is less than 20 per cent."
For women in their late 30s, it often takes longer than six months, Dr Fisher said.
ADHB chief executive Ailsa Claire said: "We regret the distress caused to the patient involved and unreservedly apologise.
"Auckland DHB is taking the recommendations outlined in the commissioner's report very seriously and will be prioritising actions to address them. A number of changes have been made to the system since 2010, when the incident occurred, to improve processes and minimise the risk of such errors from happening again."
