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Undercurrent · Deep Dive · Population & Demographics · Part II

Three Waves
of Technology

The path from sex to a child now has more off-ramps than any generation in human history. We have built an architecture of opt-in reproduction, but the mechanisms we rely on to execute that option are fundamentally broken.

ContraceptionIVFEgg FreezingDating AppsAI Companions
460%
Egg freezing increase
UK 2010–2016
16%
Return to use
frozen eggs
0.72
South Korea TFR
2023
28%
Gen Z sexual
inactivity rate

For the entirety of human history prior to 1960, reproduction was an opt-out system. Pregnancy was the default biological outcome of partnered sexual activity.

Today, reproduction in the developed world is entirely opt-in. The default outcome of modern adulthood is childlessness, and having a child requires a sequence of deliberate, sustained, and increasingly expensive interventions. This shift did not happen by accident. It is the result of three distinct waves of technology that have systematically decoupled sex from reproduction, extended the perceived window of fertility, and finally, substituted the very relationships required to conceive.

01
Wave 1: Technologies of Decoupling

The Pill and Abortion Severed Sex from Reproduction

The first wave of reproductive technology fundamentally altered the demographic trajectory of the Western world. The approval of the oral contraceptive pill (1960 in the US, 1961 in the UK) and the subsequent legalisation of abortion (1967 in the UK, 1973 in the US) severed the historical link between sexual activity and childbirth.

The demographic impact was immediate and precipitous. As economists Claudia Goldin and Lawrence Katz demonstrated in their seminal 2002 paper, The Power of the Pill, access to oral contraceptives among single women led directly to a later age at first marriage and greater representation in professional careers. The pill had a direct positive effect on women's career investment by almost eliminating the chance of becoming pregnant, thus reducing the "cost" of having sex.

Impact on Total Fertility Rates

UK Total Fertility Rate
2.86
1965
1.81
1975
36% decline in just ten years
US Total Fertility Rate
3.65
1960
1.77
1975
Similar pattern across developed world

We made it frictionless to delay reproduction, but extraordinarily difficult to catch up. The asymmetry between the £10 pill and the £10,000 IVF cycle is the defining economic reality of modern fertility.

This created a profound asymmetry. Preventing pregnancy via the pill costs approximately £10 per month and requires swallowing a tiny tablet. Reversing that delay later in life via IVF costs £5,000 to £10,000 per cycle and requires months of invasive medical procedures.

02
Wave 2: Technologies of Extension

IVF, Egg Freezing, and The Illusion of Time

If Wave 1 allowed us to delay reproduction, Wave 2 promised to extend it. In vitro fertilisation (IVF), egg freezing, and fertility tracking apps are marketed not just as medical treatments, but as insurance policies against the biological clock. The problem is that these technologies suffer from a severe moral hazard: they create false confidence that biological limits can be engineered away, encouraging further delay. When individuals finally attempt to use these technologies, they discover a massive gap between marketing promise and clinical reality.

The Egg Freezing Illusion

Elective oocyte cryopreservation (social egg freezing) has exploded in popularity, with cycles increasing by 460% in the UK between 2010 and 2016, and by 880% in the US. It is frequently offered as a corporate perk by major tech companies, framed as the ultimate tool for female empowerment. The clinical data tells a much darker story.

A comprehensive 2023 cohort study at Guy's Hospital in London tracked women undergoing social egg freezing between 2016 and 2022.

37.1
Mean age at freeze
Meaning the average woman is freezing her eggs after the biological cliff has already occurred
16%
Return to use
Of women who ever returned to use their frozen eggs
35%
Live birth rate
Per embryo transfer among those who returned

Egg Freezing Attrition Funnel

100%
Start freezing cycle
84%
Eggs successfully frozen
16%
Return to use frozen eggs
5.6%
Achieve live birth

A 2025 study from UCLA Health found even lower utilisation rates, with only 5.7% of women returning to use their eggs within a 5-year follow-up period.

The IVF Expectation Gap

A similar false confidence surrounds IVF. According to a 2020 survey presented at the European Society of Human Reproduction and Embryology (ESHRE), 85% of female IVF patients overestimate their chances of success, on average by 34 percentage points.

Age GroupActual Birth RatePatient ExpectationsOverestimation
18–3435%~59%+24 pp
35–3725%~55%+30 pp
38–3917%~48%+31 pp
40–429%~40%+31 pp
43–445%~30%+25 pp

Per fresh embryo transfer using own eggs. Latest 2023 data from Human Fertilisation and Embryology Authority (HFEA).

Beyond Google

Because the cultural narrative focuses heavily on celebrity pregnancies in their late 40s (which almost exclusively use donor eggs, a fact rarely disclosed), the general public believes IVF is a reliable backstop. For women aged 40–42, the live birth rate per fresh embryo transfer is just 9%. For women aged 43–44, it collapses to 5%.

The App Trap

Even natural conception is now mediated by technology. Fertility tracking apps like Natural Cycles (which boasts a 93% typical use efficacy rate for contraception) have gamified the menstrual cycle. However, a critical appraisal of 140 menstrual tracking apps published in the Journal of Obstetrics and Gynaecology Canada found that most calendar-based apps "did not comply" with evidence-based fertile window identification.

These apps contribute to the illusion of control. They suggest that conception is merely a matter of data optimisation, masking the underlying reality of declining oocyte quality and sperm counts.

03
Wave 3: Technologies of Substitution

Dating Apps, AI, and the Destruction of Partnership Formation

The final, and perhaps most insidious, wave of technology does not deal with reproduction directly. Instead, it attacks the prerequisite for reproduction: partnership formation. Dating apps and digital intimacy platforms have fundamentally altered the architecture of human connection.

The Dating App Business Model

Match Group, the conglomerate that owns Tinder, Hinge, OkCupid, and Match.com, generated $3.48 billion in revenue in 2024. Their stated mission is to "Spark Meaningful Connections for Every Single Person Worldwide."

However, the business model of a publicly traded dating app is structurally opposed to long-term matchmaking. Revenue is derived from paying subscribers (13.8 million as of late 2025). If the algorithm perfectly matched every user with their ideal life partner on day one, the company's revenue would go to zero.

The platform is financially incentivised to maximise engagement, time-on-app, and subscription renewals—not to remove users from the dating pool.

By presenting users with a theoretically infinite pool of potential partners, the perceived cost of committing to any single person rises. Why settle when the next swipe might yield a 5% better match? The result is a dating culture characterised by endless browsing, ghosting, and algorithmic burnout.

The Rise of Digital Intimacy

As the friction of real-world dating increases, a growing cohort of young adults is opting out entirely, substituting physical relationships with digital alternatives. The statistics on Generation Z sexual inactivity are unprecedented in modern recorded history.

Generation Z Sexual Inactivity

Young Men (18–29) with No Partnered Sex in Past Year
28%
by 2024

More than doubled since 2010

Trend

Young women are following a similar, though slightly less steep, trajectory. According to the US General Social Survey and recent Kinsey Institute data.

This void is rapidly being filled by artificial intimacy. A 2022 study published in the National Library of Medicine found that frequent pornography consumption in men is strongly correlated with a reduced frequency of partnered sexual activity and with being single.

AI Companions: The Frictionless Relationship

More recently, AI companion apps have exploded in popularity. Replika, one of the leading AI companion platforms, reported over 30 million users by late 2024. A 2025 survey found that 28% of American adults claim to have had at least one intimate or romantic relationship with an AI.

These platforms offer the emotional validation of a relationship with none of the friction, compromise, or vulnerability required by human partnership.

04
The Leading Indicators

Japan and South Korea: The Endpoint of Wave 3

Japan: The Herbivore Men

The phenomenon of sōshoku-kei danshi ("herbivore men")—young men who have entirely lost interest in dating, sex, and marriage—was identified as early as 2006.

Today, Japan also grapples with 1.5 million hikikomori, individuals who have completely withdrawn from society to live reclusive, digitally mediated lives.

South Korea: Demographic Collapse

Total Fertility Rate (TFR)
0.72
2023
0.80
2025 (slight rebound)

The friction of dating has become so severe that local governments are now offering citizens up to $38,000 simply to start a relationship and have children, while simultaneously hosting state-sponsored speed dating events.

Beyond Google

South Korea represents the absolute frontier of this crisis. With a total fertility rate of just 0.72 in 2023 (rebounding slightly to 0.80 in 2025), the country is experiencing demographic collapse. The government is now offering substantial cash incentives and creating institutional mechanisms to force pair formation. Yet nothing has worked. This suggests that the problem is no longer about friction or information — it's structural.

05
The Compounding Effect

Three Waves, One Outcome

Wave 1: Decoupling

Made pregnancy an active choice rather than a default outcome, allowing us to delay.

Wave 2: Extension

Created the moral hazard of false confidence, convincing us that biology could be paused indefinitely.

Wave 3: Substitution

Is now destroying the prerequisite for reproduction by replacing the friction of human partnership with the frictionless engagement of algorithms and AI.

By the time the average couple in the developed world decides they are ready to navigate past the dating apps, overcome their digital dependencies, and finally opt-in to reproduction, they frequently find themselves relying on Wave 2 technologies that simply do not work as advertised.

We have engineered a society where every incentive points toward delay, and every technology provides an off-ramp. The result is exactly what the math dictates: a collapse in the probability of human reproduction.

The population collapse is not the result of a single failure. It is the compounding effect of three technological waves operating in sequence, each one appearing beneficial in isolation but devastating when combined.

One Takeaway

We built an infrastructure that makes it free and frictionless to avoid having children, but expensive and complicated to have them. Egg freezing sounds like insurance but works for only 5.6% of women who try it. IVF success rates are a fraction of what people expect. And by the time you decide you're ready to commit to a partner, you might be with an AI chatbot instead of a real person.

The Dinner Party Line
"We've created three waves of technology that systematically destroy reproduction. First, we made contraception so easy that delaying became the default. Then we promised that egg freezing and IVF could pause biology indefinitely — they can't. Finally, we replaced real dating with algorithmic swipe apps designed to addict you, and when those fail, we offer AI companions. By the time you realize you want children, the window has closed and you're talking to a chatbot."
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Deep Dive · Part 2 of 5 · Population & Demographics · March 2026

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