Dookhan, 35, of Franklin was charged in September with obstruction of justice and falsifying her academic credentials. An assistant attorney general said at the time that the charges were "preliminary" and that a "much broader" investigation was being conducted.
On Tuesday, a Boston Municipal Court judge granted a motion filed by state Attorney General Martha Coakley's office asking that a pretrial hearing scheduled for Dec. 3 be rescheduled to Dec. 20.
In the motion filed in court, prosecutors said the continuance was being sought because "a grand jury investigation is on-going with indictments expected" after Dec. 3.
The motion said Dookhan's defense attorney agreed to the continuance.
Dookhan, who is free on $10,000 bail, hasn't responded to repeated requests for comment. Her attorney, Nicolas Gordon, did not respond Tuesday to requests for comment.
Brad Puffer, a spokesman for Coakley, also declined to comment on whether the indictments could include additional charges against Dookhan.
The Department of Public Health lab where Dookhan worked was shut down in August after state police took over as part of a state budget directive and discovered that the problems in Dookhan cases went beyond some isolated irregularities.
Coakley's office is conducting a criminal investigation, while state Inspector General Glenn Cunha is reviewing whether the problems at the lab went beyond Dookhan and her immediate supervisor.