https://old.reddit.com/r/stupidpol/comments/1qgrl0f/59_of_trans_women_imprisoned_in_the_uk_were/

A parliamentary written submission that compiled UK prison data found that 76 out of 129 trans women prisoners (approximately 58.9 %) were serving sentences for sexual offences when the report was written.

A much higher share than for other prisoners. For comparison, only about 3.3 % of the general female prison population were sex offenders, and around 16.8 % of male prisoners were sex offenders in the same dataset.

https://committees.parliament.uk/writtenevidence/18973/pdf/