The sperm of all 18-year-olds should be frozen for use in later life because of the risks attached with being an older father, a UK bioethicist has argued.

Sperm becomes more prone to errors with age, increasing the risk of autism, schizophrenia and other disorders.

Dr Kevin Smith, from Abertay University in Dundee, says sperm-banking on the NHS should "become the norm", reports BBC.

The British Fertility Society said such a move would "provide a very artificial approach to procreation".

It called for a greater focus in the UK on supporting young couples to have work and have children.