Now for the caveats: In wealthy, English-speaking countries the differences between the two groups vanish. Both rated their happiness around 7 on a scale of one to 10. It’s in the lower-income countries where the contentment of parents takes a dip relative to their childless peers.
The surveyors theorize that in these countries parents have children to help with farm work and household chores, “even when, on a purely personal level, they would rather not do so.” It’s this lack of choice that diminishes contentment. In other words, the pain of child rearing will feel like a pleasure so long as it’s self-inflicted.