Health inspectors are investigating potential criminal offences at an NHS trust over the deaths of three babies.
It follows the announcement of a separate police investigation into maternity cases of "potentially significant concern" at the Trust.
While it did not specify which cases were being investigated, the NUHT, which is fully co-operating with the enquiries, said the probe related to three serious incidents dating back to 2021.
The trust is currently the subject of a separate independent review into failings in maternity care and has previously been prosecuted by the CQC.
Lorraine Tedeschini, CQC director of operations, said: "We are currently in the process of making enquiries to establish whether there is reasonable suspicion that a criminal offence has been committed.
"Those enquiries are ongoing and we will report further as soon as we are able to do so."
The independent review into maternity care at the trust, led by Donna Ockenden, is set to be the largest in NHS history with around 1,800 families and 700 staff coming forward to share concerns.
Nottinghamshire Police said on Thursday that it was preparing to investigate whether anyone was criminally culpable for failings at the trust, after meeting with Ms Ockenden.
The trust’s chief executive, Anthony May, has "committed to fully co-operate" with the police investigation, the force said.
Commenting on the latest CQC investigation, Michelle Rhodes, chief nurse for NUHT, said: "The Trust is currently providing information to the CQC to support their investigation of three serious incidents which occurred in 2021.
"We are co-operating fully and will await confirmation from the CQC as to whether they intend to pursue a formal prosecution."
In papers served before an open board meeting due to take place on Thursday, the trust said: "The Trust is currently providing information to the CQC to support their investigation of three serious incidents which occurred in 2021, following notification of potential failure to comply with Regulation 12 (Safe Care and Treatment) and 22 of the Health and Social Care Act 2008 (Regulated Activities) Regulations 2014 and Regulation 20 (Duty of Candour)."
The papers also reveal there are 23 open maternity serious incidents as of August 24 this year.
In January, the trust was fined £800,000 for failures in the care of Wynter Andrews, who died 23 minutes after being born at the Queen’s Medical Centre in Nottingham in September 2019.
The trust also admitted failures in the care of Wynter’s mother, Sarah, as part of the same prosecution, which was also brought by the CQC.
In that case – the first time NUHT was criminally prosecuted – the trust admitted being a registered person who failed to provide care or treatment in a safe way resulting in harm or loss, contrary to regulations 12, 22(2) and 23(4) of the Health and Social Care Act 2008 (Regulated Activities) Regulations 2014.
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