The world's 7 billionth person will be born Oct. 31 in India, according to a projection by researchers working with data from the United Nations.
Medical advances, more effective vaccines, antibiotics and improvements in public-health conditions has boosted life expectancy in developing countries, where most of the population growth is taking place, according to the U.N. data reported in the journal Science.
The number of people globally reached 1 billion in 1800, then 2 billion in 1925, the report said. Within the last half century, the population boomed to just under 7 billion from 3 billion. By 2050, the population will reach 9.3 billion, and 97 percent of the growth will be in less developed regions, said David Bloom, an economist at Harvard University in Cambridge, Mass., who wrote the report.
"In the 1960s and 1970s, people expected a population bomb," Bloom said in a telephone interview. "Now, we have mini-bombs going off in the most fragile parts of the world. Issues of inequality and poverty may spill over from less- developed countries, which will not be good for their neighbors or the rest of the world."
Since 1970, population growth has slowed to 1 percent per year from a little over 2 percent, according to the U.N. date. Still that means that by 2050, India will overtake China as the most populous country in the world, and the U.S. will be the only developed nation among the 10 most populated.