Children as young as nine will be allowed to take drugs to block puberty, which doctors say provides a crucial delay to allow them to decide whether to undergo gender reassignment later.
The treatment, which suspends the hormonal changes that cause puberty, will be offered by one NHS trust to children with gender identity disorder (GID), where a person is born one sex but feels that they should be the other.
But the decision was attacked by critics who described the decision to offer the treatment at such a young age as “horrifying” and called for an immediate investigation.
Monthly injections of the drugs, known as hypothalamic blockers, are used to slow the development of the children’s sexual organs by blocking the production of the hormones testosterone and oestrogen.
In boys this prevents the voice from lowering and the development of facial hair, while in girls it stops the menstrual cycle and breast development, in each case making any future sex change operation simpler.