I love how the original post says this happens across vastly different societies regardless of all these different variables people are offering as possible explanations. For example, in India (which this article is about), women have a much lower rate of workforce participation than other industrialized countries. I think a lot of people who are replying are men and don't understand how physically tasking and painful pregnancy is. It seems like most women are fine having two if there's a high chance they'll make it to adulthood and they have access to family planning/contraceptives. That makes sense to me. Not sure why this is so confounding to people. Not much more of an explanation needed than that lol