I imagine nobody has this data, but presumably the correlation between birth control / women’s empowerment and lower birth rates is because maybe most humans were conceived unintentionally? Like, what’s the moral implications of most people being accidents, is that a massively taboo topic or is it just so uninteresting that nobody talks about it?
But there is a difference between a married couple intentionally creating a large family and a married couple that likes to fuck and didn’t intend to marry each other in the first place until a baby came along.