The survey of 93 women who were convicted in Sweden of sexual offences between 1988 and 2000 indicated that 37 per cent of the women had been treated at a psychiatric clinic during the period, and eight percent had been diagnosed as having a psychosis.
During the same period, 8 500 men were convicted of sexual offences.
The researchers also studied drug abuse and compared the results with more than 20 000 randomly selected women in the general population and some 13 000 women who were convicted of non-sexual crimes over the same period.
Psychosis and drug abuse prevalent in females
The findings suggested that psychosis was 16 times higher amongst the sex offenders than the control group, while drug abuse was 23 times higher.
Co-author Niklas Langstrom, associate professor at Karolinska Institute's Centre for Violence Prevention, said "it seems as if female sex offenders, more so than male, suffer from mental illness or have drug problems,"
A possible recommendation was that "women suspected or convicted of sexual offences should undergo routine psychiatric examination" which is not always the case, the researchers said.
Sexual offence was defined as "rape, non-consensual sex, sexual abuse and sexual molestation."
The full study Sexual Offending in Women and Psychiatric Disorder: A National Case-Control Study by Seena Fazel, Gabrielle Sjostedt, Martin Grann, and Niklas Langstrom was due to be published in the online edition of Archives of Sexual Behaviour. – (Sapa, May 2008)
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