A PREGNANT policewoman died of natural causes while giving birth to her twins, a coroner ruled today.

Pc Sarah Underhill, 37, of Didcot, died at Oxford’s John Radcliffe hospital in October last year after suffering a rare and fatal pregnancy condition, just hours before she was to be induced.

Doctors raced to deliver her IVF twins, Hannah and James, by emergency Caesarean section when they found her unconscious in a toilet.

Last night, her police sergeant husband Richard Underhill, 39, said it was heartbreaking the twins would never know the wonderful mother she would have been.

The two-day inquest, which began yesterday, heard that Mrs Underhill, who was brought up in Wallingford and worked as a policewoman in Marlow, suffered from an Amniotic Fluid Embolism.

Experts said the condition was nearly always fatal, unpreventable and undiagnosable and still regarded as an Act of God. It occurs when amniotic fluid, foetal cells, hair or other debris enter the mother’s bloodstream via the uterus, triggering an allergic reaction.

In Mrs Underhill, it caused massive blood loss and her heart and lungs to collapse.

Oxfordshire coroner Nicholas Gardiner said AFE was a natural condition and her death was due to natural causes.

Outside court, family solicitor John Coughlan read a statement on behalf of Mr Underhill, who also attended the inquest.

In the statement, he thanked the hospital staff for fighting to save his wife.

He said: “Sarah was a devoted daughter, caring sister and a beautiful wife.

“It’s truly heartbreaking she won’t be able to go on to be the wonderful mother she would have been and will be sadly missed by all her family.”

Mr Gardiner heard that Mrs Underhill’s ward had been staffed with one midwife and a student on October 5, the night she died, which midwife Lynn Sawyer said was not ideal.

He also heard there was a slight delay in receiving blood for her, but neither of these factors were found to be contributory to the death.

Hospital managers said an internal and external review had been carried out since the death, so lessons could be learned.

Ruth Adam, the hospital’s head of clinical risk, said more emergency blood was now kept on the ward and that staff could now open locked toilet doors with a new device to access patients in trouble more quickly.

Mr Gardiner asked hospital managers to review the emergency buzzer system in the toilet, to make sure the sound was loud enough to alert staff if there was a problem.

Gill Walton, head of midwifery, said: “This was a very sad and distressing case.

“Medical and midwifery staff did everything they could and delivered the twins safely.

“Despite their efforts, this appears to be one of the those occasions when it was not possible to reverse the tragic outcome. Our thoughts are with Mrs Underhill’s family and their twins.”