[greaterthan3]

Birth rates are low pretty much everywhere in the developed world, but South Korea is an outlier in how low they are. For example, Japan's fertility rate is 1.3, compared to Korea's 0.84. That's a huge difference.

It's possible there's something unique to South Korea that causes it. Perhaps it's mandatory 2 years of military service for males. Or maybe their famously judgmental culture. I don't know.

[eliben]

As an opposite data point: in Israel, military service of 3 years is mandatory for males, 2 years for females. Israel has BY FAR the highest fertility in the OECD. So military service probably isn't a strong correlation here.

[bigDinosaur]

The highest fertility rates in Israel, by far, are in groups exempted from mandatory military service.

[barry-cotter]

> Among Jews, the TFR among Haredim has fluctuated around 7 children per woman since the 1980s, and around 2.5 children per woman among the secular and the traditional who identify as not religious. However, Haredi fertility in the 2007 to 2013 period was lower than in the 1990s, while fertility in the non-Haredi Jewish population has increased since then.

> Even among Jewish women who self-identify as secular and traditional but not religious, the combined TFR exceeds 2.2, making it higher than the TFR in all other OECD countries.

https://www.taubcenter.org.il/en/research/israels-exceptiona...

[greaterthan3]

The fact that it's both men and women in Israel could be significant. I heard stories about people meeting their romantic partners in the army during the mandatory service.

[jxramos]

Yah I could see that. Opposite sexes commingling during the strength of youth required for military duties and which also happens to coincide with peak fertility. I’m convinced that peak fertility and sexual urges during our 20s is no coincidence—-it’s our bodies screaming a large signal at us that this is the time. That strength and ability to pull all nighters sure comes in handy caring for a newborn. Taking on such a challenge 20 years past the peak without the aid of a 10 or 12 year olds helping hands is a high burden no doubt.

I’m starting to become more convince that economies which fundamentally squander this peak fertility moment will shoulder a burden that will lead to their demise. How long can we get the fertility timing wrong before we are no more? I guess we’re about to find out.

[citrusybread]

something unfortunate to keep in mind is your emotional intelligence at that age. it's clear an 18 year old is not as mentally prepared as even a 28 year old, let alone 30+ when your brain development has really hit its peak.

it's all fine and dandy to think people should be parents in their early 20s, but think about where you were at 20. did you stay with the same person? I think if you ran surveys in the west, you'd find a disproportionate amount who either didn't have anyone, or who broke up not long after. I like to think I'm a much kinder, calmer, and more self-aware person than I was at 18, or even 25.

at 30 you might be a more tired but hopefully at that point you've:

(1) dated enough to know what to look for in a partner; (2) have found that partner who is a good match; (3) have progressed enough in your work that you're less at risk at big economic suffering

I think people who try and save up in advance of kids are a little nutty - focus on your retirement, and emergency fund, they can borrow money. it's almost never an advantageous position for it to be paid off.

3 can definitely be solved by good policy. But I think it's just foolishness to suggest that people can start having kids whenever. At least in my experience and my peers' experience, finding the person who likes you enough to consider that is the blocker by a long shot. Everything else can be solved with money.

by the way, comments earlier about Israeli military service were interesting -- it makes sense to me as an accelerant in bonding, same as some university experiences. That was however not my experience in university undergrad...

[jxramos]

The culture I came from in 20th century America somehow established this significant period of prolonged adolescence as it’s been called. So I think there is some growing up to do society wise so that folks are equipped to be in optimal biological alignment at the appropriate age and not waste time dilly dallying with 20 years of unproductive living. I don’t think this was always so in past centuries and certainly not intrinsic to the 20s demographic.

Maybe our newfound prologued lifespan gave the illusion we could shift fertility out into the suboptimal band of years indefinitely. But if our economy is structured in a way that demands this shift I have to think it comes at a long term cost where we become too top heavy so to speak and have increasingly diminished returns on how much reproduction we can sustain at those biologically suboptimal band of years with whatever guarantees that may come from deferring reproduction to that better time that may never actually come.