BEIJING — China's population has grown to 1.26 billion people and is getting older, better educated and more urbanized, according to figures announced Wednesday from its first nationwide census in a decade.

The population has grown by 132.2 million or 11.7 percent since 1990, said Zhu Zhixin, director of the National Bureau of Statistics.

Birth-control policies held population growth to 1.07 percent a year, down 0.4 percentage points from the 1990 rate, Zhu said.

Urban couples and many rural families have been restricted to just one child since the late 1970s to ease the strain on food supplies and resources.

"The results of the population census fully prove that the family planning policy of China is very effective," Zhu said at a news conference. "The natural growth rate of the population declined."

Other figures disclosed by Zhu also highlighted a disturbing trend: The lopsided ratio of males to females in Chinese society is worsening.

Chinese couples allowed only one child frequently prefer a boy to tend the family plot, carry on the family name and care for them in old age.

A 1999 survey counted 117 male births for every 100 girls — up from a ratio of 111 boys to 100 girls in 1990, Zhu said.

Zhu said women may be aborting girls, despite rules banning the use of ultrasound scanners to test the sex of fetuses. Families also may not be reporting female births, he said.

"The high sex ratio of infants really is a problem that cannot be ignored. That it worries people is understandable," he said. "With the strengthening of our management work, this problem will be properly resolved."

Sociologists fear the skewed birth ratio will lead to a shortage of brides, worsening prostitution and the kidnapping and sale of women for marriage.

Figures still to be tabulated from the census are expected to show that China's migrant population also has increased. More than 100 million Chinese, many of them poor farmers, have left home looking for work.

Most Chinese — 64 percent of the population — live in the countryside, the census found. But the proportion of city dwellers increased by nearly 10 percentage points over 1990 to 36 percent.

China is also becoming better educated, the census found.

Just 6.7 percent of people ages 15 and above are illiterate, down from 15.8 percent in 1990. The share with a university education has grown 154 percent since 1990 to 3,611 out of every 100,000. The proportion of Chinese who attended secondary school also increased.

The census also confirmed that the proportion of older Chinese is growing. Nearly 7 percent are aged 65 or older — up 1.4 percentage points since 1990.

Experts fear this trend could strain China's ability to care for the elderly, especially when one-child birth limits leave many people without siblings to help take care of their aging parents.

Some 6 million census takers spread out on Nov. 1-15 to visit all of China's estimated 350 million households. Their questionnaires alone required 10,000 tons of paper.

With Taiwan, Hong Kong and Macau included, China has 1,295,330,000 people, Zhu said.

That is lower than independent estimates that put the population as high as 1.5 billion, but Zhu defended his figures as accurate.

Hong Kong has 6.8 million people and Macau has 440,000. Both are former European colonies that returned to Chinese rule in the late 1990s.

Taiwan, with 22.3 million people, has been ruled separately for all but four of the last 100 years. But China claims the island as part of its territory. Zhu said Taiwan population figures came from the island's government.