The groups that are still growing are those that oppress women. Islamic countries [1] and ultra-orthodox Jews, especially. Evangelical Christians used to be higher but have now dropped down to the below-replacement US rate.
Teen pregnancies are way down in the US. So are abortions; that's not it.
Nobody really understands why. There's lots of speculation. The decline of religion? Better birth control? Video games? Declining testosterone levels? Fewer people in agriculture?
[1] Fertility rate 2.9. https://en.wikipedia.org/wiki/Muslim_population_growth
[2] Fertility rate 6.2. https://geopoliticalfutures.com/israeli-population-increase-...
[3] https://www.patheos.com/blogs/anxiousbench/2018/06/faith-fer...
"go read this book which explains my point because I can't explain it well enough to others." is not a convincing argument in the least.
The claim that the wealthy are controlling everyone's fertility is as short-sighted as it is parochial.
Given that elsewhere in this thread you explain how this is all the work of a shadow government, the label hardly seems unwarranted.
There is no cabal of They. The "shadow government" thesis is straight-up conspiracy batshit.
Unless you mean the Standing Committee of the National People's Congress of the People's Republic of China who certainly authorized the two-child law just a few years back, but they're not really a shadow government. They're a regular one, just not very transparent.
Ultimately both Chinese communism (via Hegel) and Western feminism (via Wollstonecraft) trace their origins back to the French Revolution, so maybe you are being controlled by Robespierre.