To stereotype the poorest countries with the custom of large family sizes is to turn a blind eye to history. Most people now living in richer countries will discover similar fecundity in their own families by tracing back just a few generations.
The circumstances might have had much in common with contemporary African countries – poverty and high child mortality, dependence on surviving children for economic support, lack of education or job opportunities for women and the unavailability of any form of contraception.
The evolution to lower fertility rates experienced in developed countries correlates with their improving social and economic circumstances. This demographic transition reflects how access to modern medicine combines with greater choice in work, education and lifestyle to lessen the appeal of large families.
In the transition from high to low fertility and mortality rates, the latter has invariably outpaced the former. The consequence is a rapid rise in national population. When the birth rate finally stabilises at its lower level, a country’s population profile will progressively age as the “baby boom” generation matures.
Countries around the world find themselves at very different points within the demographic transition. The headlong rush towards the UN’s projection of a peak global population of almost eleven billion masks a complex mix of underlying trends.
The countries of sub-Saharan Africa are at an early stage of the transition, where child mortality and life expectancy indicators are improving but the average fertility rate of 4.6 children per woman remains high.
The contrast with richer countries is dramatic. The fertility rates in North America and Europe have fallen below 2.1, the threshold for natural population replacement. The same is true of China, so that half of the world’s people live in a country or area where the population is falling. The strength of this demographic transition is such that the rate of growth of the world’s population has been falling for some time. From a peak of 2.1% per annum in the 1960s, the rate has halved to 1.1%.
Nonetheless, the demographic transition in a hard core of about 20 high fertility countries is slow-moving, with rates remaining stubbornly high. Countries such as Nigeria and Democratic Republic of Congo seem to be trapped in a demographic vortex by poverty and conflict.
more Population briefings (updated August 2021)
World Population Projections
Opposition to Family Planning
Overpopulation or Overconsumption?
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