The number of reported mistakes at IVF (in vitro fertilisation) centres in England and Wales has doubled over one year, rising from 182 in 2007/08 to 334 in 2008/09. Incidents range from technical failures to serious mix-ups. Cases where embryos have been lost, implanted into the wrong patient, or fertilised with the wrong sperm have all been reported.

The Human Fertilisation and Embryology Association (HFEA), the regulatory body of fertility clinics in the UK, said the figures represent less than one per cent of the more than 50,000 treatments carried out. The HFEA said the rise in reported errors was in part due to the extended scope of reporting - clinics are now required to include incidents from patients suffering from ovarian hyper-stimulation syndrome (OHSS), an acknowledged clinical risk in IVF.

However, fertility expert Dr Sammy Lee from University College London believes the errors raise concerns about the HFEA's ability to properly regulate the IVF industry and claims the authority is failing to enforce procedures correctly. He said, 'They need to obtain staff that have experience of enforcement and are able to make sure that regulations are put into place'.

In order to avoid potential mix-ups, clinics such as the Hewitt Centre for Reproductive Medicine in Liverpool use a bar coding system to track sperm samples, eggs and embryos. Whenever the samples are used in procedures, the tags are read to confirm they match the patient's. If they do not, the system sounds an alarm to alert the embryologist.

Dr Steve Troup, the scientific director at the centre, told BBC News Online this was a more effective and reliable system than traditional manual labelling. He explained the increased level of security justified the additional cost to patients. According to the BBC, several experts in the industry have called for the system to be made compulsory at all clinics.