There is a small but growing group of people in the US who are concerned that civilisation might collapse if people don’t have enough children. They’re called pro-natalists, and they argue that less children will lead to fewer workers and smaller economies, leading to an eventual collapse. Their solution: to save humanity people simply need to have kids. High-profile supporters of the movement include tech bros like Elon Musk and Donald Trump.

The BBC’s population correspondent Stephanie Hegarty tell us more about the movement and how it came about. We are also introduced to the Collins family, one of the leading pro-natalist families who want to have as many children as they can.

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