A sperm bank is being sued by three families in Canada who allege they were given sperm from a man with a criminal record and significant health issues.

Women in Britain and the US are thought to be among at least 36 who have got pregnant using his sperm in the last decade.

Now three Canadian families have filed a lawsuit saying US-based Xytex Corp and Ontario's Outreach Health Services misled them.

"It's horrifying," said lawyer James Fireman. "These couples were seeking assistance to build a family and were very vulnerable, they put their faith in the (cryobank) industry, and this happens."

The plaintiffs, whose allegations have not been proven in court, are seeking $11.7m (€10.3m). They say the companies lied about the donor's IQ, said he was extremely healthy and was doing a PhD in neuroscience engineering.

The families learned his true identity when Xytex inadvertently included his contact information in an email to them. An internet search and subsequent investigation revealed he was actually a 39-year-old Georgia man who had been diagnosed with schizophrenia, narcissistic personality disorder, drug-induced psychotic disorder and significant grandiose delusions.

The man had been jailed for burglary and other crimes. According to the claim, the companies continued to sell his sperm even after being informed of the discrepancies in 2014.

The sperm bank says it's looking forward to successfully defending itself.