The world population doesn't look like it's going to stop growing anytime soon. New research finds that the earth's population count is likely to hit around 10.9 billion in 2100, whereas earlier estimates suggested that it would cap off at closer to 9 billion. Currently, there are over 7 billion people on the earth.

Most of the growth is predicted to come from Africa, which the researchers say will grow from 1 billion today to around 4 billion at the end of the century. This is likely because family size is still large there, and there's still a significant and unmet need for contraception. Populations almost everywhere else aren't expected to grow anywhere near as much, with Europe, North America, and Latin America remaining below 1 billion each. Asia is currently at 4.4 billion, but it's only expected to hit around 5 billion in 2050 and then start to decline.

The estimates are all based on life expectancy and fertility rates. How those two factors are changing is going to make the biggest difference in what actually becomes of the population, and the researchers suggest that some of the population increase might be reduced by investments in family planning programs and the distribution of contraception.

It may well be important that governments of the world do that, too. "Rapid population growth in high-fertility countries can create a range of challenges," the researchers write. That could include the depletion of natural resources, issues with unemployment, increased rates of child mortality, growing crime, and broad infrastructure issues.