They were informed that a full report would not be available until the end of January at the earliest and may be delayed until mid-February.
Mr Halappanavar has now agreed to delay any possible European Court action.
The Boston Scientific worker and his solicitor, Gerard O'Donnell, met Minister James Reilly in Athlone on Thursday.
"He didn't have a preliminary report, which we had hoped for before Christmas. That was a disappointment but he informed us that he should have the full report within weeks," said Mr O'Donnell.
The HSE investigation has now interviewed all the people involved in the care of Ms Halappanavar at University Hospital Galway.
"The minister seemed sure he would get the final report by the end of January or mid-February at the latest."
Savita Halappanavar died of septicaemia on October 28 following a miscarriage.