A pregnant woman jailed for playing a bridal part in a sham marriage will be at risk of dire mecical consequences if she stays behind bars any longer, a top judge was told today.

Despite expecting her third child, Nadesa Mirgova, 26, was handed a 16-month jail term at Burnley Crown Court earlier this month after she wed a Nigerian immigrant for cash.

Her barrister, Alan Wolstenholme, made a mercy dash to London's Appeal Court in a bid to win her immediate release on bail, arguing that both mother and unborn baby are at risk of medical disaster at Styal Prison, near Manchester.

Now 27 weeks pregnant, Mirgova has endured two difficult births in the past, said the barrister. Her first baby was born "perilously early" at just 28 weeks gestation and her second was also premature and badly under-weight when delivered.

Mr Wolstenholme told Mr Justice Nicol she should be freed immediately so that she can undergo regular foetal growth scans at Central Manchester University Hospital and tests for high blood pressure and "placentral abruption" that could threaten her baby.

The judge refused her bail after hearing that Mirgova is being cared for in the prison's hospital wing, but he did order an emergency Appeal Court hearing of her challenge to her sentence, which Mr Wolstenholme said was "too long in any event".

Her case is now expected to be heard by three Appeal Court judges in the first week of March.

Mr Wolstenholme argued her sentence should have been suspended in light of her pregnancy, guilty plea, remorse and co-operation with the authorities.

Putting Mirgova behind bars earlier this month, Judge Beverley Lunt said she had "chosen to become pregnant" by her boyfriend soon after her arrest for the part she played in a sham marriage at St Andrew's Church, Accrington, in May 2009.

Mirgova married Olarotimi Ojugbele, 41, at the church where a number of fake marriages have been exposed. Ojugbele had been jailed for 21 months at an earlier hearing.