The Demographic Transition Model

• The demographic Transition model is a conceptual model that describes changes in population structure.
• It is based on observed changes in transitions in birth and death rates in industrialised countries over the last 200 years.
• It has four stages 
• The transitions started in Europe at around 1800.
• Before the transition, lives were short, births were high, the population was young and growth was slow.

• Stage 1 is called the Pre-Modern stage
• It took place in the 18th century (1700's)
• Birth and death rates were high
• Population growth was slow
• The population was young
• Food shortage
• Disease 
• Drought
• Children contributed to household income
• Lack of knowledge of disease prevention or cure.

• Stage 2 is called the industrialisation or urbanisation stage
• 19th century (1800's)
• Birth rates were still high
• Mortality declining - reduction of contagious and infectious diseases spread by water or air
• Child mortality first to decline, followed by infant mortality - smallpox vaccination
• Decline in adult mortality more gradual
• Population explosion
• Improved access to food - introduction of potatoes and maize
• Changes observed in NW Europe

• Stage 3 is called the mature industrial stage
• 20th century (1900's)
• Fetility rates starting to decline
• Mortality rates declining further
• Increasing urbanisation
• Female literacy and education improved
• Better access and availability of contraception
• Population stabilised

• Stage 4 is called the post-industrial stage
• 21st century (2000's)
• Population gradually declining
• Birth and death rates decreasing further
• Fertility rates dropped below replacement level (2.1)
• Population structure older

The factors that triggered fertility decline are...

• Erosion of norms supporting high fertility
• Expensive childcare
• Children no longer contributing to household income
• Reduction in child mortality
• Improvments in contraception
• Increasing number of women joining the labour force