The second-child policy pushed China's total fertility rate up to more than 1.7 last year, an increase from between 1.5 and 1.6 between 2000 and 2015.

Wang Pei'an, deputy minister in charge of the National Health and Family Planning Commission, told a news conference on Saturday that the increase was due to the new policy adopted at the beginning of last year allowing all couples to have a second child.

More than 18.4 million babies were born in China last year, the highest number since 2000, Wang said.

The fertility rate is the average number of children a woman gives birth to in her lifetime.