[toomuchtodo]

Birth rates are a component, but so is per capita environmental impact. Lower total fertility rates everywhere are welcome [1], but if one were to prioritize efforts, you'd focus on highest per capita environmental impact (whether that be CO2 emissions, consumption beyond replenishment rate of natural resources, etc).

I'll go so far as to say that empowering women through education and family planning access alone in some countries isn't enough; you might have to provide direct cash payments to assist in developing agency through career development or entrepreneurial efforts. Otherwise, from my research [2] [3], they're beholden to their partner's family wishes (which may not align with their own, and they may not have the safety or security to assert their will).

[1] https://ourworldindata.org/fertility-rates/

[2] https://theconversation.com/family-size-why-some-nigerian-me... ("Family size: why some Nigerian men want more children")

[3] https://www.scientificamerican.com/article/africa-s-populati... ("Men also have to relinquish sole control over the decision to have children and refrain from abusing wives or partners who seek birth control.")