The variations in fertility rates across regions have a significant impact on population growth. Fertility declines in many countries have led to a deceleration in population growth globally. Sub-Saharan African countries are projected to experience the most significant population increase, while other regions are expected to see a decline in population growth in the second half of the century. Factors such as improved education, women's empowerment, and access to family planning services have contributed to declining fertility rates.Population momentum, which results from the existing age structure, plays a crucial role in future population growth. Most countries are projected to continue growing in the short term, with sub-Saharan Africa accounting for a substantial portion of the global population increase. The future trends in population growth are influenced by fertility, mortality, migration, and other factors, leading to uncertainties in population projections.The world's population is urbanizing rapidly, with over half of the global population living in urban areas. Urbanization trends vary across regions, with substantial growth expected in developing countries. The growth in the number of households with decreasing sizes is another notable trend, impacting energy consumption, environmental sustainability, and long-term development goals.Overall, understanding and addressing the variations in fertility rates and their impact on population growth are crucial for sustainable development and achieving global goals. Policymakers need to consider these trends in formulating effective policies to manage population growth, urbanization, and household dynamics while promoting sustainable development and addressing environmental challenges. source