Mental health professionals missed opportunities over the care of a Bristol University student who was found hanged on the day of an important practical assessment, an independent expert has told her inquest.

Dr Laurence Mynors-Wallis, a consultant psychiatrist, said he could not understand why experts had downgraded Natasha Abrahart’s case from high risk even though she had tried to kill herself at least twice.

He said the lack of an adequate plan for Abrahart’s treatment may have contributed to her death and suggested failings had meant she was not given hope of recovery.

Abrahart, 20, a second-year physics student who had social anxiety disorder, was found dead at her shared flat on Park Street near the main university campus on 30 April last year.

She is one of 12 students at Bristol University who have or are suspected of having killed themselves since September 2016.

Abrahart’s parents, Margaret, a retired psychological wellbeing practitioner, and Bob, a retired associate professor at Nottingham University, have expressed deep misgivings about how Bristol University and health professionals looked after their daughter.

Mynors-Wallis was instructed by the senior Avon coroner, Maria Voisin, to examine the treatment provided by Avon and Wiltshire mental health partnership NHS trust.

On the fourth day of the inquest, he said a university GP who saw Abrahart on 20 February following an apparent suicide attempt was correct to conclude she was at high risk.

But as soon as she was referred to mental health experts, her condition was downgraded and she was not seen by a member of the north Bristol assessment and recovery team until 23 February. “I’m not clear why it was downgraded,” he said. Abrahart was finally assessed by a trainee but no clear treatment plan was put in place, Mynors-Wallis said.

Abrahart returned to see a second university GP on 21 March after another apparent suicide attempt. Again, the doctor took swift action to get her help.

This time she was seen the following day, but a member of a mental health crisis team concluded she was not at significant risk.

The crisis team member decided Abrahart should speak to a “recovery coordinator”, but he then went on holiday and has said there was nobody else to arrange this.

When he returned from holiday, he allocated the role to someone who then also went on holiday. Abrahart was not seen by the recovery coordinator until 26 April. Mynors-Wallis said he found it “quite shocking” that when someone was on leave, their work was not covered.

Abrahart died on 30 April on the day she was due to present a physics experiment in a lecture theatre with 43 other students and two academic markers present.

Mynors-Wallis said Abrahart wanted help and always attended her appointments. “She was not pushing help away,” he said.

The consultant psychiatrist concluded: “On the balance of probabilities, failure to provide a timely and detailed management plan represents a causal connection with her death.”

The inquest continues.

• In the UK, Samaritans can be contacted on 116 123 or emailjo@samaritans.org. In the US, the National Suicide Prevention Lifeline is 1-800-273-8255. In Australia, the crisis support service Lifeline is 13 11 14. Other international suicide helplines can be found at www.befrienders.org.