Getting data on the highest poverty areas, (like sub-Sahara Africa countries.) Is difficult. Many of the countries themselves can not and/or will not collect this kind of data.
Data on US pregnancy is a lot easier to find, (some of the highest rates of poverty and teenage pregnancy in any industrialized “first world” country especially in poorer areas of the country like the “bible belt.”)
" Only 38 percent of girls who have a child before age 18 get their high school diplomas by 22."
" Seventy-eight percent of children born to teenage mothers who never married and who did not graduate from high school live below the federal poverty level. "
Moving on to what I can find on the very poor, < 2 dollars a day we find:
Oke, Yetunde F., Poverty and Teenage Pregnancy: The Dynamics in Developing Countries (November 29, 2010). OIDA International Journal of Sustainable Development, Vol. 2, No. 5, pp. 63-66, 2010, Available at SSRN: https://ssrn.com/abstract=1717155
I did not read through that article however.
An easier, less dense article from WHO
Agreed, it is hard to find any real data on this sort of process. I am aware that in many of the poorest districts, it is entire extended families looking out for each other and entire communities. The ones that do not have that, simply die, quite often completely unrecorded.
In my own personal experience: I have gone off the beaten tourist path in sub-saharan Africa, and I saw younger family members that would literally chew food for most of the elderly population, that lacked teeth to chew unprocessed food. Even after spending a huge amount of effort to “mill” the grains/rice/etc.
Every remote village I visited, I saw a lot of home made fermented foods (alcohol) that quite often was the best way to give these elderly the calories they needed to survive. (I tried some and it tasted awful to me.) I saw tons of kids just “wandering around,” usually naked or near naked, and my driver/guide told me the entire village “dressed” in their sunday best and partied in anticipation of my group’s arrival.
Don’t worry non religious, which really weirded out a lot of these people, where their only contact with “rich white people” was almost always accompanied by strong religious motives.
All that said, I saw local orphanages bursting at capacity, there is millions of children in these countries that were abandoned by parents. With widespread birth control, these numbers could go down, and some couples could choose to adopt and fill a major need (unadopted children that have horrible poverty life outcomes typically,) to care for them in older age.
You hear often times in the news of celebrities adopting children from places like this, but realize that is a 1 in a million sort of scenario. 99% go on to live entire lives of extreme poverty, with very poor average life spans.
All of this got 10x worse since covid came along is my understanding. (If you want I can see if I can find any data to back this particular claim.)