Jailed mothers' children 'damaged'
More than 17,000 children were separated from their mothers after the women were sent to jail last year, new figures show.
No women should be sent to prison, but those convicted of violent offences should be held in local secure units instead, the Howard League for Penal Reform said.
Its estimates showed more than 17,240 children under 18 were forcibly separated from their mother in England and Wales in 2010.
The separations, caused when mothers were jailed, can cause long-term emotional, social, material and psychological damage, often with little to no dedicated support, the Howard League said.
Its Voice of a Child report found that more than 11,000 children could be spared the problems if non-violent women were not sent to jail.
Frances Crook, the campaign group's chief executive, said the "real answer is to take women out of the very establishments that will hinder their and their children's life chances".
"Women should not be in prison in the first instance," she said. "The best way to reduce women's offending is in the community, by improving mental health services and tackling drug abuse."
Half of all women prisoners have children under the age of 18, figures from the Chief Inspector of Prisons showed.
More than 4,000 women were behind bars in England and Wales last week, Ministry of Justice figures showed. But more than half the women entering prison did so on remand and, of those, three in five did not receive a custodial sentence, the campaigners said.
A Ministry of Justice spokeswoman said: "Prison sentences can be distressing for the children and families of female offenders. That is why we want to increase confidence in community sentences - to demonstrate they are a viable option for non-violent offenders with caring responsibilities."