There are a growing number of people speaking out about their decision not to have children because of climate change. They worry about the environmental impact of bringing a new person into the world. But how polluting is it to have kids? And is staying childfree a good way to limit how much carbon dioxide we put into the atmosphere?

The BBC’s Georgina Rannard talks us through some research from University College London. And researcher Johannes Ackva, from the Founder’s Pledge, brings us a study he co-wrote looking at how different lifestyle choices - including flying, driving a car and having children - impact the climate. He thinks that, as governments’ net-zero pledges really start to ramp up, emissions per person will likely go down - and this could impact how polluting it is to have babies in the future.

Plus, we hear from three people who’ve decided not to have kids: Nirupama Kondayya, and husband Vipin Nair from India now living in the UK, and a woman from the US.

Email: whatintheworld@bbc.co.uk WhatsApp: +44 0330 12 33 22 6 Presenter: Hannah Gelbart Producers: Maria Clara Montoya and Mora Morrison Editors: Emily Horler and Simon Peeks