In countries without proper health care, the lives of everyone lower than upper-middle class are unbelievably precarious. In the US at least, although there was a lot less healthcare 100 years ago, there were no procedures that cost you 10 years salary.
Just giving birth in the US costs about $20K. It takes a day, and can be done at home by professionals that don't even need to be trained as nurses at 99% of the safety level. It can be done by a woman alone, with no help, at 80% of the safety level. If you can wring $20K out of something that generally happens by itself without a hitch, your system is fucked up.
Life is precarious here, although often luxurious. Exchange that luxury for security, and you'll see a lot more people confident enough in the future to have a baby responsibly. It's not a question of having a suburban yard, it's a question of having something that won't be pulled out from under you quickly. The suburban yard is just a buffer, just like close family that live nearby is. But capitalism atomizes the family, and encourages them to move to find work on a dime. Capitalism is a direct competitor to the family: family is where capitalism isn't. The larger families are, the less capitalism exists.
SK is a US vassal state, so I can't imagine that their health care system is much more humane.