Surinder Venables, 49, died a month after a routine operationA woman died after a gynaecologist perforated her uterus during a 'routine' operation, a hearing was told.
Surinder Venables was due to have three cysts removed at Basildon Hospital, but died after Dr Nikolaos Papanikolaou mistakenly removed part of her bowel.
The 49-year-old, from Basildon, was stabilised after the procedure on September 25, 2008, but suffered further complications and died a month later after suffering a cardiac arrest.
Dr Papanikolaou did not warn the patient of the risks involved, did not carry out the procedure correctly and failed to recognise his mistakes, which resulted in her death, the hearing was told.
He also left swabs in other patients and failed to carry out vital caesareans which, in one case, led to a still birth, it is claimed.
Dr Papanikolaou has admitted the charges in relation to Ms Venables and another patient, but denies a series of other allegations relating to five women while he was working at Basildon and Thurrock General Hospitals NHS Trust in Essex between 2008 and 2009.
Alexandra Felix, from the GMC said: 'This is a case about a doctor who has displayed deficient clinical assessment with outcomes that were sub-optimum.
'This is not based solely on outcomes but also objectively in his approach to record keeping and what happens to swabs.'
One patient went to see her doctor after Dr Papanikolaou performed a procedure on her and she was left with an unpleasant odour.
Miss Felix said: 'Patient HC began to complain of a very nasty smell and she went to a doctor for examination.
'Having done so, a large swab was removed.'
Nurses noticed there were not enough swaps accounted for when examining another patient and again found one had been left inside the woman.
Dr Papanikolaou also failed to perform a caesarean when an obese pregnant woman came into hospital and the child died.
'A baby was delivered with a cord around its neck and a still birth was recorded,' said Miss Felix.
'The overall standard of care fell seriously below standards expected of a specialist registrar.'
Surinder Venables went to Basildon Hospital, Essex, to have three cysts removed, but part of her bowel was removed by mistake
The GMC did not become aware of Dr Papanikolaou's blunders until 2010 when a patient's father complained to the Basingstoke and North Hampshire Hospitals NHS Trust about the treatment of his daughter when she was giving birth to a baby girl.
Investigations revealed a series of blunders and the doctor's 'careless' approach to record keeping.
'Dr Papanikolaou's record keeping in general is of a poor standard. He has shown a tendency to write notes retrospectively,' said Miss Felix.
'He has demonstrated mismanagement in decision making in relation to patients.
'His poor standard of care is demonstrated by the leaving of swabs in patients.'
Dr Papanikolaou is not attending the tribunal and is not represented after his defence withdrew following a submission to adjourn proceedings.