Ninety million of the 140 million child-bearing age women who have been married and given birth to a child would now be allowed to have a second.
Prior to the introduction of the two-child policy, more than 38 per cent of the population were expected to be older than 60 by 2050. Beijing hoped the two-child policy could reduce this by two percentage points, Wang said. He added that the labour force would increase by 30 million by 2050.
The two-child policy would boost economic growth by 0.5 of a percentage point, a study by the Chinese Academy of Social Sciences estimated.
Wang said that the new policy had already provided a boost to the maternity industry, which had been performing well in the stock market recently.
After reaching 1.45 billion the population would drop back to 1.38 billion in 2050, Wang said, but the pressure of overpopulation would remain
China delayed scrapping its one-child policy out of fear that the population would expand too rapidly, a senior official said despite the fact demographers say the birth rate was already dwindling before it was introduced in 1979.

Brian Wang is a Futurist Thought Leader and a popular Science blogger with 1 million readers per month. His blog Nextbigfuture.com is ranked #1 Science News Blog. It covers many disruptive technology and trends including Space, Robotics, Artificial Intelligence, Medicine, Anti-aging Biotechnology, and Nanotechnology.
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