If Michelle had committed her shoplifting offence in Moscow she would have received a suspended sentence until her daughter reached the age of 14; in Finland she may not have been sent to prison at all. However, because she was convicted of shoplifting in Scotland, and because she already has a long history of offending, she was sent to Cornton Vale prison for three months.

Michelle is dependent on heroin and her four-year-old daughter is dependent on her. In many ways she is relieved to be sent to jail, a stable environment where she will be able to escape her abusive partner.

She feels so much safer in prison, in fact, that to ensure she stays there she indulges in wilful fire-raising on the inside.

Michelle's details are fictitious, but her story is one highlighted in a new EU-funded report which reveals that women are, in some cases, choosing to go to prison and to stay there.

The question is how could these women's lives be allowed to get so bad that they would choose incarceration over freedom?

A prison inspector said: "One woman I met in jail who was there on remand told me her trial date was coming up the next week so she was trying to get her lawyer to arrange a postponement because the advice was that she was going to be found not guilty.

"She wanted it to be postponed so she could stay in for longer because she felt safer in prison."

The details of the report make for sombre reading. It paints a picture of chaotic drug-abusing women, many of whom have been sexually abused in the past, most of whom have no GP on the outside, no job and no home.

The Scottish part of the study was conducted by Dr David Shewan, co-director of the Centre for the Study of Violence at Glasgow Caledonian University. It involved in-depth interviews with female prisoners, health experts, staff and the governor at Cornton Vale.

One of its recommendations is that non-violent female offenders should not be sent to prison at all.

Ministers have made consistent pledges to reduce the female prison population but in the past decade it has more than doubled and is one of the fastest-growing in Europe.

Almost 5% of Scotland's burgeoning prison population is made up of women, a far higher proportion than that in France, Uganda, Libya, Afghanistan, Poland and Nigeria. In fact, out of 196 countries, Scotland comes 89th, not a ranking to be proud of for a developed country.

In May last year, the daily female prison population peaked, with 365 women behind bars. On the same day in 2002, there were just 273 women in jail.

A report by the Scottish Consortium on Crime and Criminal Justice, an umbrella body bringing together leading organisations concerned with crime and criminal justice in Scotland, revealed that female offenders sent to prison on remand each year increased by 80%, from 1009 in 1996-7 to 1807 in 2003-4.

The EU-funded report comes nine years after a report commissioned by the government called for a significant reduction in the numbers of women sent to prison in Scotland and concluded most were sent there for minor offences such as fine defaults.

In 1998, the government-commissioned report on women offenders, A Safer Way, stated: "The number of women offenders sent to prison could and should be reduced. The only relatively sure method is to make a significant reduction in the number of women being imprisoned. The aim should be to limit the female population at Cornton Vale to 100 or less on a daily basis by the end of 2000."

In Russia, mothers convicted of most crimes, particularly those with young children, are given a suspended sentence until the child reaches 14. In Spain, wives are allowed to stay in prison with their husbands, and in Finland, which has a similar population to Scotland, the government has worked to reduce the prison population by diverting most sentences to community alternatives.

"It is a tragedy that hundreds of women are coming into prison and it is certainly the case that women will seek ways of staying in," said Dr Andrew Fraser, head of care and health within the Scottish Prison Service. "In an odd way prison may be safer for them than the outside. This provides a challenge to people out there to fashion a life in communities which is more attractive than prison and not the other way around.

"The accused opt for prison because it is an assured method of getting access to services and means some of them will get another chance. The question is why? Is this because of a lack of suitable alternatives outside or a lack of awareness about the suitable alternatives?

"For many of them the prospect of leaving prison is disturbing because of what they left behind. Some women have worked in prostitution and know that the small amount of money they are given on leaving prison will be taken from them by partners or pimps, so they immediately have nothing to make a new start."

In his latest report on Cornton Vale, Scotland's only women's prison, Dr Andrew McClellan, the chief inspector of prisons, concluded that, of the inmates, 98% had drug addiction problems, 80% had mental health problems and 75% had a history of abuse and very poor physical health.

Women in Cornton Vale also have 14 times more dental decay than those in the community - an indication of heroin addiction and poor health generally.

"We are locking up increasing numbers of increasingly damaged women," Dr McLellan told The Herald. "It is desperately sad. You see it not just in their eyes but on their arms, which are deeply scarred from a long history of self-harming.

"We should not be sentimental about the nature of the offences women commit. My last report showed that for the first time more than 50% of those in Cornton Vale were there for crimes of violence, but we do have to question why this is happening.

"It is also much more difficult to be a woman prisoner in Scotland and maintain family contact than for a man, because the women are held on a central site."

Mental health and addiction problems characterise these women, and many experts claim the experience of prison is likely to increase their drug-taking and offending.

Many of them are still being imprisoned for minor offences. Seven out of 10 prison sentences passed on women are for six months or less.

In 2004-5, more than 400 women were sent to prison for failing to pay a fine.

The report states: "The primary conclusion to draw from Scotland is that the prison system is heavily over-burdened and under unacceptable levels of pressure. The commonly held view is that this particularly applies to the female prisoner population. The level of damage and disadvantage among this group is very high.

"The level of drug use is such that it could be identified as the main problematic characteristic of the female prisoner population. The incidence of mental health problems are, when compared to the general population, equally striking.

"One suggestion made by all participants was that of finding ways to keep non-violent female offenders out of prison."