About 10.6 million children were born last year, a decrease of 12 percent from 2020 when 12 million births were reported.
The country's total population at the end of 2021 was estimated at 1.413 billion people.
That is 480,000 more than the year before.
The pace of population growth has slowed over the past decade.
This makes the country fear a demographic "time bomb", with too few able-bodied people to be able to support a growing proportion of older people.
In 2021, the proportion of working age (16–59 years) was just over 62 per cent of the population, a decrease of 8 percentage points over the past ten years.
The Communist Party introduced birth control in the 1980s.
Despite the country easing its one-child policy in 2015, high costs, overcrowding and discrimination against women who become mothers have discouraged parents from having more children.