Children as young as nine are to be prescribed drugs which delay the onset of puberty as the first step towards a sex change operation, according to reports. The treatment will be offered by one NHS trust to children who are so troubled by their gender that they may wish to undergo drastic surgery after adolescence, according to the Mail on Sunday. 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. Andrew Percy MP said: ‘I think many people will be horrified at the thought of a nine-year-old being provided with a drug that effectively stops them developing and maturing naturally.’