Edit: Since people seem to think I’m saying abating climate change causes fewer children, I’m not. Communication is not my strongpoint - but I have a B.B.A in Econ with an emphasis in Sustainable Supply Chains, and a Master’s in Quantitative Finance, so let me rephrase this. Countries that implement more policies to fight climate change are typically populated by people who care and are educated about climate change, who are also less likely to have more children due to the current path humanity is on.

Something vaguely related to this topic is the fact that countries with more laws designed to abate climate changing effects are also experiencing a slowdown in the rate with which they have children. Whereas many countries with relatively high birthrates generally do not have very strict climate standards. Overall levels of general education also play into this.

Tldr; Generally, the more people know about climate change, the less likely they are to have children.