Low rates of natural increase can be due to high death rates from ward or diseases(HIV/AIDS). It could also be due to young adults migrating out of the country leaving the country with an ageing population who are no longer able to have children. Low rates of natural increase could also be due to the country having an anti-natalist policy. As the country becomes more advanced contraceptives may become more accessible which lowers the birth rate or the population may be more educated and have a better understanding on family planning.