Page 7 - Aspire April -2023 Vol 8 / Issue 2

CLEARLY EVIDENT IN SOUTH EAST ASIA
“These older citizens and the economies that support
them need to be sustained by the productivity of decreasing numbers of young people in the workforce who are time poor and facing their own growing cost- of-living pressures.
“Rampant urbanisation with its pressures on space to house a family, social distractions, the economic cost of raising children, and wider access to contraceptives are driving population decline.
“Furthermore, as countries become more prosperous, women of reproductive age desire to contribute to society in more ways than just having children. They are pursuing education and career paths on journeys of self fulfillment to realise their own potential in life.”
Professor Aitken said the main drivers of population decline were:
• socio-economic factors driven in part by the changing roles of women and their decisions to delay starting a family thereby putting their own fertility at risk while many others voluntarily commit to childlessness;
• environmental factors and atmospheric contaminants that pose threats to human health. For example, sperm counts in men are in serious global decline and new patterns of disease associated with environmental oestrogens have emerged in prosperous societies including the increased prevalence of testicular, breast and uterine cancers; and
• more long-acting genetic factors.
“In paleolithic times, parents would need to have seven children for one or two to survive,” he said. “There were high birth rates, but also high death rates.
“Today there is no selection pressure on fertility at all. You don’t need a large family for your genotype to survive, so selection pressure on high fertility genotypes is reduced and we become less fertile.
“What role does IVF play in this? Let’s say roughly fifty per cent of infertility is genetically determined. If we perform IVF at scale, the more you use this technology the more you are keeping poor fertility genotypes in the population.
“This is why I say, the more we used assisted conception in one generation, the more we are going to need it in the next.”
Professor Aitken said in some countries such as Australia, the political response to falling TFRs was to implement immigration programs to “balance the population books”, but he believes this is simply shifting the problem around and a short-term fix.
Atmospheric contaminants pose a threat to human health and fertility in men and women
“In biological rather than political time, there may be major geopolitical and economic consequences to the decline in TFR” he explained.
Professor Aitken points to China as a leading example of a country that has lost what he calls “population momentum.” “In China, one of the consequences of the one child per family policy was that there was no population momentum, meaning there is not a reservoir of young girls reaching sexual maturity to buffer population numbers.
“As a result, the population will decline very fast. China’s prosperity is very much dependent on population growth so who knows what the ramifications will be in that country let alone globally among its major trading partners.”
Professor Aitken believes the first response is for societies to recognise the driving forces behind rapidly falling fertility rates, and to then address them at socio-economic, environmental and genetic levels.
Responses may include:
• parental support schemes for mothers and fathers in the workforce to have children earlier as introduced in Scandinavian countries;
• baby bonus incentive payments from governments as Australia introduced successfully in 2004 to encourage young couples to have children;
• income tax reform to ease cost of living pressures on working people of reproductive age; and
• an increased availability of affordable housing.
Professor Aitken will deliver the Bruno Lunenfeld Lecture entitled The Decline and Fall of Human Fertility in the opening session of the ASPIRE 2023 Congress in Adelaide on Friday 8 September.
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