Malcolm and Simone Collins hope to have 10 children to help avoid what they see as a pending demographic collapse. They tell Lucy Hockings that as pronatalists they want to promote the dangers of falling fertility rates and encourage other people to have more children.

Whereas many people might see their lifestyle as extreme, pronatalism seems to be gaining support at the heart of the Trump administration. But some people worry that some pronatalist practices cross the line into eugenics and that the far right are also adopting the ideology. Our correspondent in Washington, Nomia Iqbal, helps us to put it all in context.

Producers: Richard Moran and Mhairi MacKenzie

Technical producer: Frank McWeeny

Assistant editor: Sergi Forcada Freixas

Senior news editor: China Collins