Fertility & Mortality Rates
The demographic transition in numbers. Fertility dropped from 5.0 (1950) to 2.3 births/woman (2024). Life expectancy soared from 46 to 73 years. The drivers of population change.
Key Fertility & Mortality Insights
Fertility Collapse Accelerating
Global fertility fell from 5.0 (1950) to 2.3 births/woman (2024)—below replacement (2.1) by 2030s. 52% of countries (108 nations) already sub-replacement. South Korea (0.72), Singapore (1.0), Italy (1.2) lowest. Sub-Saharan Africa (4.3) last high-fertility region, declining fast.
Mortality Revolution Complete
Life expectancy surged from 46 years (1950) to 73.3 (2024)—gain of 27 years in 74 years. Infant mortality plummeted 93%: from 385/1,000 births to 27/1,000. Maternal deaths down 44% since 2000. Infectious diseases gave way to chronic diseases (heart, cancer) as top killers.
Regional Gaps Persist
Life expectancy gap: 85 years (Japan, Monaco) vs 54 years (Chad, Nigeria). Infant mortality: 3/1,000 (Iceland, Japan) vs 80/1,000 (Sierra Leone, Somalia). Sub-Saharan Africa faces double burden—high infectious disease deaths + rising chronic disease. COVID-19 reversed 2 years of gains globally.
Drivers of Decline
Fertility drop driven by: female education (10 years schooling = 1.5 fewer births), contraception access (64% of couples use modern methods), urbanization (urban fertility 30% lower), delayed marriage (median age 26→30), rising costs. Mortality fall: vaccines, antibiotics, sanitation, nutrition.
Global Fertility Rate 1950-2100
Total fertility rate (births per woman)
Key Finding: Fertility halved from 5.0 (1950) to 2.3 (2024), projected to reach 2.1 by 2035 (replacement level), then 1.8 by 2100. Decline accelerated post-1970 due to contraception revolution, female education expansion. Implies population peaking mid-century.
Fertility by Region (2024 vs 2100)
Births per woman by major region
Key Finding: Sub-Saharan Africa (4.3 → 2.1) will complete transition by 2100. East Asia already lowest (1.3), projected to stabilize at 1.5. Europe (1.5 → 1.6) slight recovery assumed. All regions converge toward 1.5-2.0 range by century's end.
Countries by Fertility Rate (2024)
Highest and lowest fertility nations
Key Finding: Niger (6.7), Somalia (6.1), Chad (5.8) highest—driven by low contraception use, early marriage, rural populations. South Korea (0.72), Hong Kong (0.8), Singapore (1.0) lowest—high education, delayed childbearing, housing costs, work culture. 108 countries sub-replacement.
Life Expectancy 1950-2024
Years at birth, global and by region
Key Finding: Global life expectancy rose from 46 (1950) to 73.3 (2024). Europe leads (78 years), Sub-Saharan Africa lags (62). HIV/AIDS crisis (1990s-2000s) reversed SSA gains. COVID-19 (2020-21) caused largest single-year drop since WWII, recovering by 2024.
Infant & Child Mortality Decline (1950-2024)
Deaths per 1,000 live births (under-5 and infant)
Key Finding: Under-5 mortality plummeted 94%: from 214/1,000 (1950) to 38/1,000 (2024). Infant mortality down 93%: 385 → 27/1,000. Driven by vaccines (saving 4M annually), ORS (oral rehydration), antibiotics, improved nutrition. 5M children still die annually—mostly preventable causes.
Causes of Death Transition (1990 vs 2024)
Share of global deaths by cause category
Key Finding: Communicable diseases (infections, maternal, neonatal) fell from 44% (1990) to 22% (2024) of deaths. Non-communicable diseases (heart, cancer, diabetes) rose from 50% to 71%. Injuries stable at 7%. Epidemiological transition complete in high-income countries.
Understanding Fertility & Mortality Metrics
Key Indicators
Total Fertility Rate (TFR): Average births per woman during reproductive years (15-49). TFR of 2.1 = replacement level (population stable without migration).
Life Expectancy at Birth: Average years a newborn is expected to live given current mortality rates. Not a prediction (improves over time).
Infant Mortality Rate (IMR): Deaths under age 1 per 1,000 live births. Indicator of healthcare quality, sanitation, nutrition.
Under-5 Mortality Rate (U5MR): Deaths under age 5 per 1,000 births. Broader health system indicator.
Maternal Mortality Ratio (MMR): Maternal deaths per 100,000 live births. Reflects obstetric care quality.
Demographic Transition Theory
Stage 1: High birth + high death rates → stable population (pre-industrial)
Stage 2: Death rates fall → rapid growth (early development)
Stage 3: Birth rates fall → slowing growth (urbanization, education)
Stage 4: Low birth + low death → stable (developed countries)
Stage 5: Birth < death → decline (Japan, Germany, Italy today)
Why Fertility Falls
- Education: 10 years female schooling reduces TFR by ~1.5 births
- Contraception: Modern method use rose from 9% (1960) to 64% (2024)
- Child Mortality: Lower infant deaths → less need for "insurance births"
- Urbanization: Children economic burden in cities vs asset in rural areas
- Women's Employment: Opportunity cost of childbearing rises
- Delayed Marriage: Marriage age rose from 21 to 26 globally
Data Sources & Methods
Fertility data from vital registration (births), household surveys (DHS, MICS), census. Mortality from death certificates, sample registration, verbal autopsies. UN harmonizes 200+ country datasets. Confidence intervals widen for projections—2100 fertility 80% likely between 1.5-2.3.