In IB Geography, the Demographic Transition Model (DTM) illustrates the transformation of a country’s population over time through changes in birth rates and death rates. Each stage reflects distinct shifts in population growth, mortality, and fertility patterns, closely linked to levels of economic development, urbanization, and social change.

Why is this important? Understanding the DTM is essential for predicting population structure, planning resource allocation, healthcare, education, and economic policy.

It also explains population phenomena such as the demographic dividend—a period of accelerated economic growth due to a favorable working-age population ratio.

Stages

The model is divided into five stages:

• Stage 1 (High Stationary): Characterized by high birth rates and high death rates, resulting in slow population growth. This stage represents pre-industrial societies with limited medical knowledge, poor sanitation, and subsistence farming. Population size remains relatively stable but vulnerable to famine, disease, and war
• Stage 2 (Early Expanding): Death rates begin to decline rapidly due to improvements in healthcare, sanitation, and food supply, while birth rates remain high. This causes a rapid population increase. Many developing countries are currently in this stage
• Stage 3 (Late Expanding): Birth rates start to fall due to factors like increased female education, urbanization, and access to contraception. Population growth begins to slow. Economic development and improved living standards encourage smaller family sizes
• Stage 4 (Low Stationary): Both birth rates and death rates are low and stable, leading to a balanced population with slow or no growth. This stage is typical of developed countries with advanced healthcare systems and high levels of female participation in the workforce
• Stage 5 (Declining): Some countries experience birth rates falling below death rates, causing population decline. Factors include aging populations, lifestyle changes, and economic pressures. Japan and some European countries exemplify this stage

Key insights

• Stage 1 and 2: High birth rates often occur before economic development and female empowerment
• Stage 4 and 5: Low death rates are seen as societies become medically advanced

Flaws of the DTM: Like any model, it has its weaknesses. For the DTM it’s been criticized as eurocentric, oversimplified and assumes a linear model.

All covered in my notes.