By Ravindran Jegasothy, Pallav Sengupta, Sulagna Dutta and Ravichandran Jeganathan
Climate change has long been a major factor affecting health and the economy of the world. In the 21st century these effects have become more pronounced. Over the next decades, researchers expect significant environmental vicissitudes such as rising annual temperatures, increasing sea levels, rainfall fluctuations and extreme weather events in Malaysia and many other countries.
Moreover, as research has shown in the past, climate change seems to have an effect on fertility: either directly, by affecting reproductive functions and neuroendocrine regulation, or by affecting the immediate environment, socioeconomic status, quality of food and water and other factors.
In Malaysia, climate change is considered as a major cause for the emergence and cessation of various infectious conditions. In addition, over the last three decades, the country has been experiencing a gradual decline of the total fertility rate, which is currently below 2.1 and thus not sufficient to sustain the present population levels. However, neither the exact causes of the declining fertility rate in Malaysia nor potential measures to maintain the national population have been adequately investigated yet.
To address this, a recent article, published in the Journal of Basic and Clinical Physiology and Pharmacology, discusses the possible mechanisms of how climate change in Malaysia may be associated with the nation’s fertility.
The Invisible Enemy
According to the researchers, besides extreme climate events like forest fires, floods, heat waves, draught, storms etc., there are silent climate modifiers like global warming, which may have immediate or long-term disruptive effects on health and fertility. Since the reproductive system functions optimally only at a definite temperature range, any factors that alter the ambient temperature can thus impede normal reproductive functions.
Climate change may also meddle with the ambient air quality whereby toxic contaminants soar in the air. These air pollutants may jeopardize physiological homeostasis, disturb metabolism, redox balance and hormonal milieu, and can ultimately result in a state of compromised health and the development of various reproductive disorders.
Oxidative stress is a main role player in these processes, as oxidative damage severely impairs the functions of our reproductive glands. It affects gametogenesis (the production of sperm and egg cells) and chromatin integrity, and can induce germ cell death. This, in turn, leads to altered semen quality in men and a reduced egg quality and uterine receptivity in women.
Given the fact that a major proportion of Malaysia’s population already suffers from malnutrition, poor sanitation and contagious diseases, the impact of climate change on Malaysian health and fertility seems to be all the more worrying. To investigate the missing links further and to stop Malaysia from falling victim to the ongoing climate changes the authors encourage further research in this direction.