Something I've noticed is that many couples that do want a child have a very difficult time conceiving. People are having kids at a later age on average, but even younger couples seem to have a hard time.
Various gynecological disorders seem to be very common too - fibroids, endometriosis, adenomyosis, amongst others, all of which affect a woman's fertility.
My wife and I have been trying for a kid but have been unsuccessful. Many of our friends are experiencing the same, and are resorting to clinical fertility procedures like in vitro fertilization or artificial insemination.
I don't know how true it is, but one of my friends outright said that the majority of women in Korea are conceiving through some kind of fertility procedure, and that if we really wanted a baby, not to waste our time and just go ahead and do the same.
One thing that makes me believe him is that there are a ton of twins amongst the couples in our social circle. My understanding is that naturally twins are a rare phenomenon, but much more likely if doing something like in vitro or artificial insemination?
Us, we've already decided that push comes to shove, we'll most likely adopt.