A review is under way after four women died at Homerton Hospital’s maternity unit in the space of eight months.

It is the latest in a string of investigations at the hospital following persistent allegations from an anonymous group of whistleblowers about the avoidable deaths of mothers and babies there.

In the whole of England and Wales last year there were 47 maternal deaths during pregnancy, childbirth and the six-week period following birth.

Two of the deaths at Homerton’s maternity unit occurred in 2013 and two in 2014.

During the five years preceding there was only one maternal death, in 2012.

MP for Hackney North and Stoke Newington Diane Abbott, a former shadow public health minister, said: “These shocking statistics are yet more evidence that cuts to NHS funding are costing lives. Pay freezes and staff shortages are placing our incredibly committed and skilled midwives under intense pressure.”

The review at Homerton will be overseen internally by medical director Dr Martin Kuper.

He has asked the Medical Director at NHS England (London) to identify external obstetric and anaesthetic members for the panel to examine the four deaths collectively, alongside the usual process of investigating each case independently.

A group who dubbed themselves the “unhappy midwives” flagged up concerns about several unspecified serious incidents at the hospital, two years ago, claiming women and babies were being exposed to poor standards of care and of a culture of racial discrimination.

Results of an independent investigation by the City and Hackney Clinical Commissioning Group (CCG) launched last October should have been published in June, but were only made public last week. The reviewers concluded they were unable to substantiate any of the allegations.

Homerton University Hospital NHS Foundation Trust – which strongly denies the claims – launched its own internal investigation when the whistleblowers came to light in June 2012, reporting back in August that year it could not uphold the allegations.

However the group continued to complain, and launched an online petition calling for the resignation or removal of the senior maternity management at the hospital.

A Care Quality Commission inspection of the hospital last year, again gave the maternity unit an all clear, but the group’s persistence prompted the CCG to launch its own investigation, to try and identify specific incidents from the information provided by “unhappy midwives”.

A spokesman for Homerton Hospital University Trust said: “The trust has been finishing off the review of each individual case, with internal and external input.”

“Working with NHS England, preparations are being put in place for an overarching external review to examine the cases collectively.”