A maternity unit was severely criticised today by a healthcare watchdog following the deaths of 10 women who gave birth at the same hospital.

The Healthcare Commission blamed system failures, weak leadership and a poor quality of care in nine out of the ten cases at Northwick Park Hospital in north west London.

The watchdog renewed its call for all NHS trusts to check they have robust systems for monitoring the safety of maternity units as today's report described what happened to each of the ten women, all of whom died during pregnancy or within 42 days of giving birth between April 2002 and April 2005.

The number of deaths was more than six times the national average, where about one woman in 8,775 dies in childbirth.

The investigation into the North West London Hospitals NHS Trust found a catalogue of failings at the hospital, which had a working culture that led to poor working practices and a poor quality of care.

Difficult decisions were often left to junior staff, the report added, the hospital failed to recognise and respond quickly when a woman's condition changed unexpectedly and it had inadequate resources to deal with high-risk cases.

There were too few consultant obstetricians and midwives, and not enough dedicated theatre staff, the commission said.

The report found there was a reliance on agency and locum staff without adequate managerial or professional support and a lack of a dedicated high dependency unit.

The maternity unit also failed to learn lessons after each death and although the trust took action, the working environment was such that mistakes were repeated.

The trust's board was also criticised for failing to appreciate the seriousness of the situation.

Marcia Fry, the commission's head of operational development, said: "This was a sad and tragic series of events. We hope this report at least gives some answers to the families involved.

"At the time of the deaths, the working practices at the trust were unacceptable. However, under special measures, the trust has got its maternity services on the road to recovery.

"We will continue to work with them to ensure that they continue to progress and that everything possible is done to stop this happening again.

"We expect trusts across the country to read this report and learn the lessons.

"Most women in this country give birth safely. But there are risks and the NHS must ensure it does all it can to reduce them. There can be no excuse for failing to learn the lessons from tragedies of this kind."

In April last year, the Healthcare Commission was called in to investigate maternity services at the hospital amid concerns over the high number of deaths and an outside team of doctors and midwives was also sent into the unit to help improve the situation.

It was also put on special measures and the Nursing and Midwifery Council (NMC) withdrew approval for new student midwives to be taken on by the trust.

Today's report outlines the impact of the hospital's failings on the ten women after a report in July last year identified the system failures, including lack of leadership and weak risk management.

The Commission said there have been "significant improvements" in the maternity services provided by the hospital, including the recruitment of three further consultants and 20 midwives.

The watchdog also said it was "satisfied" that progress had been made with antenatal, post-natal and delivery services, and that working practices had improved, after it conducted an unannounced visit to the unit on August 15.

Five of the families of the 10 women, who were aged in their 20s, 30s and 40s, met the investigation team to discuss the report and a sixth family responded in writing.

The solicitor representing the husband of one of the women who died at the hospital said the report was "damning".

Louise Forsyth said 27-year-old Premalatha Jeevagan died after giving birth to her first child, a girl, in May 2004.

She said Mrs Jeevagan's husband Selvarantnam found it difficult to accept how easily his wife's death could have been avoided.

Mrs Forsyth said: "I am pleased that the provision of maternity care at Northwick Park Hospital has been fully investigated.

"However, it makes for incredibly sad reading and the findings are extremely damning.

"The report clearly concludes that the hospital did not provide an adequate standard of care to most of the 10 women who died between 2002 and 2005.

"I am especially concerned that the trust failed to learn from earlier deaths and that similar failings were found between the third death in 2002 and Mrs Jeevagan's death in 2004.

"Her death could so easily have been avoided and this is very difficult for Mr Jeevagan and his family to accept. It is difficult to understand why links between the deaths were not made, possibly enabling later deaths to be prevented.

"I am disappointed that so little attention is given to the progress made in Northwick Park Hospital maternity services in the report.

"I would have liked to see more detail about the changes that have been made so that Mr Jeevagan and all of the other families could be reassured that real changes have been made and that the deaths were not in vain.

"I hope that the trust's executives will carefully consider the comments made in the report and ensure that all of the recommendations made in the report are implemented without delay.

"The results should also be influential in the decisions taken at all other hospitals providing maternity services to ensure the safety of women being admitted to prevent a similar tragedy occurring again."

"I know my client will find it hard to read the findings, but he and his family welcome the report."

Mrs Forsyth said a coroner in Mrs Jeevangan's inquest concluded that she died because doctors failed to realise the gravity of her situation or treat it in time.

She said the inquest in February 2005 found she had died due to a delay in treatment following catastrophic postnatal bleeding.