Over 18.46 million new babies were born in China last year registering an increase of 11.5 per cent after the world's most populous nation permitted a second child scrapping the three-decade-old controversial one-child policy.

The number of newborns in 2016 was the highest since 2000 with 45 per cent being second children, Yang Wenzhuang, head of the Department of Community Family Planning with the National Health and Family Planning Commission (NHFPC) told media here.

Yang attributed the growth in 2016 to the country's relaxation in family planning rules.

However, according to data released by the National Bureau of Statistics (NBS) on Friday, the number of China's newborns in 2016 was 17.86 million, 1.31 million more than that of last year.

China scrapped one child policy last year which was in vogue since 1970s to limit the population. The government permitted second child as the country faced demographic crisis with old age population crossing 250 million already.

However the policy to permit a second child has not evoked big response as many couples felt they can not afford and cope up with second child, specially their education.

Yang said China's fertility rate is expected to fluctuate around 1.8 in the 13th Five-Year Plan period (2016-20), which will reveal the effect of the loosened family planning policy.

"The data given by the NHFPC, based on birth certificates released last year, is closer to the country's actual birth situation," Yuan Xin, a professor at Nankai University and expert on family planning policy, told the Global Times.

The full effect of the policy easing will show in the following two to three years, with around 18 million newborns annually, Yuan predicted.

According to the NBS, the population of the Chinese mainland reached 1.38 billion at the end of 2016, up 8.09 million year-on-year.

The male population is more than 708 million, whereas there are upward of 675 million women in the mainland.

The working-age population aged between 16 to 60 years old, is 907 million, about 65.6 per cent of the total population, which is expected to decline rapidly in the coming years.

China, with a population of 1.357 billion is the world's most populous nation.