Overpopulation is an issue of the past, or soon it will be. Within the scientific community, it has become increasingly apparent that the human population is reaching a point of exponential decline. This might seem dramatic, however, analysing the total fertility rate in Australia can help us to understand.
The total fertility rate or birth replacement rate, represents the number of births that can replace a population from one generation to the next. To ensure a successful birth replacement rate, women will need to have 2.1 children, one to replace herself, and her husband, and 0.1 to account for infant mortality. However, current data suggests that Australia’s total fertility rate is at 1.66, well below the needed replacement rate of 2.1.
Having a lower fertility rate also causes a decrease in population momentum – the impact that the age structure of a population has on its future size and composition. Population momentum will be revisited in the future; however, the takeaway message is there will not be enough women within their reproductive life span, to sustain the population. Therefore, a dramatic exponential decline in the human population will begin to occur.
Ironically, it is issues resulting from overpopulation that are going to lead to this downfall. It’s no secret that overpopulation has caused extensive environmental pollution in the air, water and soil, leading to the accelerated rate of climate change. This increased pollution brings about numerous environmental factors that can affect the body’s homeostasis and in turn fertility.
Low Fertility Rates are a Socioeconomic and Scientific Matter
When we look at the common causes for decreased birth replacement rates, it comes down to physical, lifestyle, environmental, and social factors. Lifestyle and social factors can go hand in hand, as different cultural and socioeconomic factors can lead to couples having more or less children by choice. Compared to the past, the work-life relationship dynamics between cis heterosexual couples have changed, with women making up almost half of the workforce in 2022, compared to less than a third in the 1960s. This has resulted in women choosing the have fewer children, and/or having children later in life, closer to the end of their reproductive lifespan.
However, reproductive biotechnology isn’t focusing on these social issues. Instead, scientists are aiming to decrease and limit infertility caused by extrinsic and intrinsic factors such as environmental-related stresses, toxicants and endocrine-disrupting chemicals. Numerous toxins can impact fertility in males and females, including Bisphenol A (BPA), pesticides, air pollution, heavy metals and parabens.
IVF, the current face of infertility treatments
Regardless of the causes, infertility has traditionally been treated using Assisted Reproductive Technologies (ARTs), such as In Vitro Fertilisation (IVF). This revolutionary biotechnological breakthrough from the 1970s has led to endless successful pregnancies, helping to combat infertility. However, IVF is a very invasive and expensive therapy, that isn’t successful in all recipients. Therefore, there is a need for new and innovative therapies.
CAPA-IVM, a new and innovative solution
CAPA-IVM (Capacitation in-vitro maturation) is a new treatment from The University of New South Wales, which recently had its first successful birth. The research, led by Professor Robert Gilchrist, is an innovation ART, involving the removal of eggs at an immature stage and maturing them in cell culture. This removes the need for patients to receive 2-weeks of hormone injections when using IVF. The less invasive approach is also expected to reduce costs for patients.
Reproductive Biotechnology beyond ARTs
Historically, there has been a focus on female factor infertility, however, with new studies finding that there is a more even split between male and female factor infertility, a new branch of focus is becoming more popular. Studies into the previously mentioned environmental factors and endocrine disruptors that cause infertility, and the impacts that these toxicants have on regular homeostasis – including hormone signalling pathways, is another key focus of reproductive biotechnology which will continue to be explored in future articles.
Although human extinction due to low fertility rates is an issue of the future and doesn’t take into account immigration, this discussion highlights the importance of reproductive biotechnology and the research that is being undertaken to combat the issue of infertility, which impacts 1 in 6 couples in Australia.