<P> The region of Sub-Saharan Africa has the highest birth rate in the world . As of 2016, Niger, Mali, Uganda, Zambia, and Burundi have the highest birth rates in the world . This is part of the fertility - income paradox, as these countries are very poor, and it may seem counter-intuitive for families there to have so many children . The inverse relationship between income and fertility has been termed a demographic - economic "paradox" by the notion that greater means would enable the production of more offspring as suggested by the influential Thomas Malthus . </P> <P> Afghanistan has the 11th highest birth rate in the world, and also the highest birth rate of any non-African country (as of 2016). The rapid population growth of Afghanistan is considered a problem by preventing population stabilization, and affecting maternal and infant health . Reasons for large families include tradition, religion, the low status of women and the cultural desire to have several sons . </P> <P> Japan has the third lowest birth rate in the world (as of 2016), with only Saint Pierre and Miquelon and Monaco having lower births rates . Japan has to deal with an unbalanced population with many elderly but few youth, and the situation is estimated to get worse in the future, unless there are major changes . An increasing number of Japanese people are staying unmarried: between 1980 and 2010, the percentage of the population who had never married increased from 22% to almost 30%, even as the population continued to age, and by 2035 one in four people will not marry during their childbearing years . The Japanese sociologist Masahiro Yamada coined the term "parasite singles" for unmarried adults in their late 20s and 30s who continue to live with their parents . </P> <P> Historically, Australia has had a relatively low fertility rate, reaching a high of 3.14 births per woman in 1960 . This was followed by a decline which continued until the mid-2000, when a one off cash incentive was introduced to reverse the decline . In 2004, the then Howard government introduced a non-means tested' Maternity Payment' to parents of every newborn as a substitute to maternity leave . The payment known as the' Baby Bonus' was A $3000 per child . This rose to A $5000 which was paid in 13 instalments . </P>

What factors affect the birth rate of a country