Adam Leylange and Jessica Johannesson had decided that 2018 was going to be the year they would try for a baby.

The couple, who live in the English city of Bath, had gone back-and-forth over that decision for all the usual reasons, including timing and money, but had finally decided, “Ok, this is when it’s going to happen,” Johannesson says. Then, in October, the UN Intergovernmental Panel on Climate Change released a report showing that the world has to start cutting emissions drastically and do it soon if we are to keep global warming under 1.5°C, after which“even half a degree will significantly worsen the risks of drought, floods, extreme heat and poverty for hundreds of millions of people.”

The report prompted Johannesson and Leylange, who were already involved in climate activism, to join BirthStrike, a mostly online community of about 300 people…