A systematic investigation of fertility around the world has recently been performed relying on 8709 country -years vital and sample registration. Age specific rates of survival were made in age groups from age 10 to 54 years. The results are indeed worrying as summarized in their results chapter.
“During the period from 1950 to 2021, global TFR more than halved, from 4·84 (95% UI 4·63–5·06) to 2·23 (2·09–2·38). Global annual livebirths peaked in 2016 at 142 million (95% UI 137–147), declining to 129 million (121–138) in 2021. Fertility rates declined in all countries and territories since 1950, with TFR remaining above 2·1—canonically considered replacement-level fertility—in 94 (46·1%) countries and territories in 2021. This included 44 of 46 countries in sub-Saharan Africa, which was the super-region with the largest share of livebirths in 2021 (29·2% [28·7–29·6]). 47 countries and territories in which lowest estimated fertility between 1950 and 2021 was below replacement experienced one or more subsequent years with higher fertility; only three of these locations rebounded above replacement levels. Future fertility rates were projected to continue to decline worldwide, reaching a global TFR of 1·83 (1·59–2·08) in 2050 and 1·59 (1·25–1·96) in 2100 under the reference scenario”. in most countries, by the end of the century, the fertility rate will be below the one needed to renew the population, with only a few poor sub-Saharian countries having a positive fertility.
The authors stress that in this scenario, there will be clear demographic division between a few poor countries and the rest of the world- including the Samoa Islands, Somalia, the Tonga Islands, Niger, Tchad, and Tadjikistan. Some countries being well below the minimal fertility generation renewal requirement -Saudi Arabia, Nepal Bangladesh. there will be rapidly a competition between rich countries to attract workers from poor countries to preserve wealth and industry. Clearly, the present messages of stopping immigration will be rapidly invalid. Also, an important message from this work is that the Malthusian prediction – the world will collapse because of over population- might well be resolved… Collectively, this again stresses the difficulty and un-reliability of previsions made relying on economic criteria without considering the development of society and the plethora of criteria needed to have a reliable image of the situation. There are many important political implications of this study!
https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(24)00490-2/fulltext
