A woman suffered a miscarriage and had to wait three hours for medical attention, detainees threw themselves down stairwells and staff used racist and sexually abusive language, according to a Channel 4 documentary into conditions at Yarl's Wood immigration removal centre. 

The documentary coincided with the release of a highly critical parliamentary report into Britain's immigration removal system which the head of the Refugee Council told Christian Today lit up some "very murky corners". 

The allegations broadcast last night were based on the work of a reporter who worked undercover at the centre for three months. It revealed a culture of racism, sexism and threats of violence, and of frequent incidences of self-harm. One woman jumped from a stairwell to escape guards who were chasing her. In another clip, a guard told of a Chinese inmate who had been imprisoned for two years and who also jumped off a stairwell, breaking her back. He said: "She had to be in a wheelchair, so they decided she got released."

The film also includes examples of racist abuse and admissions of violence towards inmates.

The parliamentary report into Britain's immigration removal system was a joint inquiry by the All Party Parliamentary Groups on Refugees and Migration. MPs and peers damned the system as not only inhumane but ineffective and wasteful.

The all-party report by members of the House of Commons and House of Lords includes fierce criticisms of the present system. At present some asylum seekers are held for long periods, with serious impacts on their mental and physical health: last year 400 people were held for longer than six months and 108 for longer than a year. Some detainees suffered torture or sexual abuse in their own countries.

The report says no one should be held for longer than 28 days and detention should be the last resort. It says the UK Government should learn from other countries such as Sweden, where alternatives to detention allow individuals to live in the community and control immigration at a much lower cost to the state.

The UK is the only country in the European Union not to have an upper time limit on detention, though Home Office guidelines say that detention should be used sparingly and for the shortest possible time.

The Parliamentary panel, which included a former Cabinet minister, a former Chief Inspector of Prisons and a former Law Lord, concluded that holding people for indefinite periods had a significant mental health impact on detainees.

It also said victims of rape and sexual violence should not be detained and that pregnant women should never be detained for immigration purposes. It said that people were increasingly being held in conditions tantamount to high security prisons.

At a briefing in Parliament yesterday, MPs David Burrowes, Sarah Teather and Paul Blomfield stressed the high degree of consensus achieved across party lines on the way the system needed to change. Teather, the inquiry chair, said: "We concluded that the current system is not working. It is expensive, ineffective, unjust and unusual – we detain more people for longer than other countries."

She said that the inquiry had heard "harrowing" evidence about the impact of detention and spoke of a "culture of disbelief" which hampered access to healthcare. "We need a whole-scale change in the system," she said.

Blomfield said: "One of the most striking things was the really harrowing evidence about the effect of the length of detentions. One person said that it was 'worse than prison'. It has a hugely destructive impact if people have no idea when they will be released." Burrowes added: "We call our detention centres 'removal centres', but people don't get removed for years. We are down the league table when it comes to giving dignity to detainees."

The chief executive of the Refugee Council, Maurice Wren, told Christian Today: "We welcome this report. It shines a strong light on some very murky corners of the UK immigration system." Home Office guidance at present, he said, was "routinely ignored or flouted".

He particularly welcomed the proposed limit of 28 days on detentions, adding: "There is a growing consensus that there is a need for proper judicial oversight."