I understand that you don't want to split hairs, and I don't want to split them merely to be difficult (or pick nits). Nevertheless, I'm not entirely convinced

I understand that you don't want to split hairs, and I don't want to split them merely to be difficult (or pick nits). Nevertheless, I'm not entirely convinced that we can avoid the distinction between the desires for sex and for children. I remain unconvinced that the driving desire is for children (or procreation, as you put it now). My argument, in a nutshell, is that we can see that the desire for sex is primary and paramount by observing human behavior. The desire for sex precedes, outlasts, contravenes and cuts across the desire for children. Beyond that, I don't think contraception is necessarily evidence for pressure to not have children, so much as evidence for a desire to control when and how many children to have. Certainly some people use contraception to avoid all children, but surely many more people use it in an effort not to have over large familes, no? As evidence for this (partial, because there are other factors like fear and permanence) consider that most people choose less reliable one-off contraception rather than a vasectomy or tubal ligation, even when both are readily available. China is one country, and in this regard somewhat exceptional.