The NHS must offer fertility treatments to transgender patients awaiting transitioning treatment or risk breaking anti-discrimination legislation, the UK’s human rights watchdog has said.

The Equality and Human Rights Commission (EHRC) accused the NHS of using a “interpretation” of its own legal powers that allowed it to deflect criticism over lack of fertility provision onto the government.

Transitioning treatment is given to patients with gender dysphoria - the feeling of discomfort or distress caused by a mismatch between biological sex and gender identity - and can result in fertility loss.

The EHRC said trans patients should be offered the opportunity to store their eggs or sperm, a process known as gamete extraction, otherwise thousands could be forced to choose between the essential medical treatment and not having their own biological children.

Fertility treatment is already available to some patients who undergo fertility-threatening procedures such as chemotherapy, to allow them to conceive afterwards.

The EHRC issued a legal letter to NHS England on Friday, claiming that the withholding of fertility treatments from transgender patients constituted discrimination. It also warned that it would take legal action if policies were not changed.