Arwa Baghdadi is about to give birth behind bars after being held in custody without charges for several months.

The dual US-Saudi citizen was arrested a day after her brother was killed during violent clashes with the security services in Saudi Arabia in late 2011, Global Voices reported.

The young mother was first detained at the Dhahban prison in central Jeddah but her supporters said she was recently transferred to the al-Hayer prison by plane despite being eight months pregnant.

Al-Hayer is a maximum-security prison facility located approximately 25 miles south of Riyadh.

They claim she is being detained for calling Saudi authorities 'infidels', a charge she denies. She has now been in jail for over six months.

Her husband, mother, father, sister-in-law, three children from their family and a member of their domestic staff were also arrested at the same time, Global Voices said.

Activists said the family was arrested during a raid a night, despite authorities having no arrest warrant.

Baghdadi, who was pregnant at the time of her arrest, was also forced to take her then one-year-old child with her to jail as her close relatives were all arrested.

Human rights groups, including the Saudi Civil and Political Rights Association (ACPRA) an independent but unlicensed human rights organization have called for her to be transfered to a hospital to give birth.

According to ACPRA , Baghdadi has been on hunger strike during her detention to protest against her custody and trial conditions.

The organisations said her detention breaches the Saudi Criminal Procedure Code after she was held for long period in solitary confinement, refused phone calls to her family or access to a lawyer.

Baghdadi has also complained about the sanitary conditions in the prison and said officers would sexually harass and ridicule prisoners who complained about their living conditions.

Many of her supporters took to Twitter to vent their anger at the case and call for her release.

"@EbtihalMubarak: Arwa Al-Baghdadi a Saudi/American detainee w/out trial"

@USEmbassyRiyadh shd interfere & ask #Saudi gov 2 allow birth & recovery in hospital", Mubarak, a Saudi journalist wrote

"@MFQahtani: The ministry of interior bears full responsibility of potential complications resulting from Arwa Baghdadi's prison birth and the refusal to transfer her to the hospital."

In a report in 2011, Amnesty international said the legal status and conditions of imprisonment of thousands of security detainees including prisoners of conscience, remained shrouded in secrecy.

"Cruel, inhuman and degrading punishments, particularly flogging, continued to be imposed and carried out. Women and girls remained subject to discrimination and violence, with some cases receiving wide media attention." it added.