Women are being conned into freezing their eggs at an age when there is almost no chance of success, research on British clinics suggests.

IVF centres were last night urged to act more ethically, after watchdogs found hundreds of women undergoing the expensive procedure in their 40s, when it was unlikely to work.

The report by the Human Fertilisation and Embryology Authority (HFEA) found clinics - which typically charge around £7,000 for egg freezing - had even authorised the procedure for those approaching 50.

The watchdog warned of a “steep decline” in fertilty after the age of 35, and said there was a “very slim” chance of success for those in their 40s.