If current fertility rates continue to rise at expected levels the world's population is estimated to increase past 9 billion before 2050. This astonishing jump is said to come from "high fertility countries" mainly in sub-Saharan Africa, but also in Asia, Oceana and Latin America. The 2010 Revision of World Population Prospects shows that a small variation in fertility may lead to extensive long term differences in the size of the international population.
While in many countries the populations are aging and will continue to do so as their fertility rates decline, the populations of countries classed as "low fertility" or intermediate fertility" are said to peak well before the end of the century. But at the same time, life expectancy in general is expected to rise across all categories of countries due to improved health care and treatment of HIV/AIDS. This cuts the probability of early death in many sub-Saharan countries. For example, Niger has one of the highest rates of population growth in the world. This is of course seen as a major improvement in global health access and is to be commended, but simultaneously is causing an enormous rise in the global population, which could possibly create further disparities in access to resources.
Currently, the number of people in the world is close to 7 billion and is believed to pass 8 billion in a mere twelve years, in 2023. By 2041 the global population will possibly have reached 9 million, and then 10 billion by 2081. But, the increase in fertility in the above countries could have major consequences and shoot the global population up to an astonishing 15.8 billion by 2100.
SOURCE: UN NEWS