Students could be withdrawn from hospitals in Essex after a controversy over standards, the Nursing and Midwifery Council (NMC) has said.
NMC chief executive Dickon Weir-Hughes said it was considering whether the hospitals provided "suitable learning environments" for its students.
A regulator found Colchester Hospital University NHS Trust consistently failed to improve waiting times.
Death rates in hospitals of two trusts were higher than expected, it said.
'Detrimental to education'
At the Colchester trust, death rates were found to be 12% higher than expected, while death rates at the Basildon and Thurrock trust were "unusually high".
There were major hygiene lapses at the nearby Basildon and Thurrock NHS Trust.
Mr Weir-Hughes said he was also concerned staff are responsible for upholding standards in the nursing and midwifery code, including managing risk and making the care of people their first concern.
"We are considering whether Colchester Hospital University NHS Foundation Trust and Basildon and Thurrock NHS Trust are providing suitable learning environments for nursing and midwifery students," he said.
"We will be discussing the situation with the universities as we have the authority to remove students if the learning environments prove detrimental to their pre-registration education."
Health Secretary Andy Burnham making a statement on standards at Essex hospitals: From BBC Democracy Live
Hospital regulator Monitor last week sacked the chairman of the Colchester trust, Richard Bourne.
A task force has been sent in to both trusts to force through improvements.
Eleven NHS foundation hospitals are currently being scrutinised by Monitor for a "significant breach" of the terms relating to their foundation trust status.
In a statement, the Colchester trust said its Members' Council is "confident" it can, with the help of new chairman Sir Peter Dixon, address Monitor's concerns.
"Delivery of the improvements expected by Monitor was not quick enough," it added.
"We believe that we will now make the progress required."
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