The use of female voices on voice-powered virtual assistants, including Amazon's Alexa, Apple's Siri, and Google Assistant, portray women as 'obliging, docile and eager-to-please helpers', reinforcing gender stereotypes of women, according to a UNESCO report.

Responses from AI assistants such as Alexa to verbal sexual harassment tend to be 'deflecting, lacklustre or apologetic', the report said, and appeared to show a greater tolerance towards sexual advances from men than from women.

The authors made a series of recommendations on how technology companies can make their virtual assistants less biased, notably by hiring more female programmers and by installing gender-neutral voices rather than making their assistants female by default.