A report into 10 maternity deaths at a west London hospital has prompted calls for urgent safety checks at NHS maternity units.
Premalatha Jeevagan died after giving birth to her first child
The Healthcare Commission's report followed deaths at North West London Hospitals Trust's Northwick Park Hospital from April 2002 to April 2005.
It highlighted a number of failures, including the lack of response to changes in patients' condition.
The North West London Hospitals NHS Trust said lessons had been learned.
The report criticised the level of care from the trust in nine out of 10 cases.
'Poor working practices'
It also said there were not enough resources to deal with high-risk cases, too few consultant obstetricians and midwives and not enough dedicated theatre staff.
It also criticised a reliance on agency or locum staff without the necessary managerial support, and the lack of an adequate high dependency unit.
Lessons learned after some of the deaths, the commission's report said, failed to be put into effect because of poor working practices.
All of the 10 women died during pregnancy or within 42 days after birth. The number of deaths was much higher than the national average, the commission said.
"The national average for maternal deaths as reported by Cemach (Confidential Enquiry into Maternal and Child Health) is one death per 8,775 maternities or 11.4 deaths per 100,000 maternities," the Healthcare Commission said.
"The maternal death rate for Northwick Park maternity unit (in the period April 2002 to March 2004) was 74.2 deaths per 100,000 maternities."
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."
Lawyer Louise Forsyth, of Irwin Mitchell solicitors, said the commission's recommendations did not go far enough.
Mrs Forsyth represents the husband of one of the women, Premalatha Jeevagan, (27), who died after giving birth to her first child, a girl, in May 2004.
"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," she said.
The trust's chief executive, Mary Wells, said changes made so far included a £19m investment to improve the maternity unit and the appointment of three new consultants, 20 midwives and a team of 10 recovery nurses.
"Clearly this has been a tragic time for all the families and I hope the report provides them with a better understanding of what happened," she added.
"I would like to reassure them, and the local community, that lessons have been learned and that we continue to do all we can to avoid tragedies of this nature happening again."