DAFENG, China — When asked why she and her husband do not want a second child, Shi Xiaomei smiles at her pudgy 9-year-old son and does a quick tally of the family budget.
Her salary as a cleaning lady and the income from a mahjong parlor in their spare room barely cover their son's school fees and other expenses.
"With just one, we can give him nicer things. But if you tried to split what we have between two or three, they would all end up with nothing," the 34-year-old says at her home in Dafeng, a prosperous but still-rural county 185 miles (300 kilometers) north of Shanghai.
For years, China curbed its once-explosive population growth with a widely hated one-child limit that at its peak led to forced abortions, sterilizations and even infanticide. Now the long-sacrosanct policy may be on its way out, as some demographers warn that China is facing the opposite problem: not enough babies.
A stroll down the dirt path linking Shi's close-knit neighborhood suggests why.
Though a little-known exception allows a second child when both parents are single children themselves, there are few takers.
"Why would we want another one? That's just looking for trouble," said Huang Xiaochen, 28, mother of a year-old son.
"Kids are running in and out of here all the time," her husband Zhu Yingzhun said, pointing to his front door which, like many here, is often left open. "He doesn't need a sibling to have someone to play with."
Officially, the government remains committed to the one-child policy. But it also commissioned feasibility studies last year on what would happen should it eliminate the policy or do nothing. An official with the National Population and Family Planning Commission said privately that the agency is looking at ways to refine the limit without getting rid of it.
A people shortage may seem unlikely in a country of 1.3 billion, the most in the world. The concern, though, is not with the overall number. Rather, as the population shrinks, which is projected to begin in about 15 years, China may find itself with the wrong mix of people: too few young workers to support an aging population.
It is a combination that could slow or, in a worst-case scenario, even reverse China's surging economic growth. The government and families will have to tap savings to care for the elderly, reducing funds for investment and driving up interest rates. At the same time, labor costs probably will rise as the work force shrinks and squeeze out some industries.
In a survey of 18,638 women in Dafeng and six other counties in Jiangsu province, 69 percent of those eligible to have a second child said they would stop at one, with economics being the major factor. The Chinese Academy of Social Sciences survey did not calculate a margin of error.
"Government control is no longer necessary to maintain low fertility," Zheng Zhenzhen, who headed the study, wrote in the November issue of Asian Population Studies magazine. "A carefully planned relaxation of the birth-control policy in China is unlikely to lead to an unwanted baby boom."
Family size has dropped dramatically since the 1970s, when the average Chinese woman had five to six children. Today, China's fertility rate is 1.5 children per woman. Most families have just one, but exceptions allow multiple children for ethnic minorities and a second one for rural families whose first baby is a girl.
If that fertility rate holds, China's population will peak at 1.4 billion in 2026 and then start shrinking, according to the U.S. Census Bureau. By the end of this century, China's population would be cut almost in half to 750 million, according to a model developed by Wang Feng, a demographer at the University of California, Irvine. That would still be two and a half times bigger than the U.S. today.
Wang says the government's focus on slowing population growth has dangerous side effects.
In just 10 years, the age 20-24 population is expected to be half of today's 124 million, a shift that could hurt China's economic competitiveness by driving up wages. Over the same period, the proportion of the population over 60 is expected to climb from 12 percent – or 167 million people – to 17 percent.
"We feel like we're seismologists, you know," said Wang, who has helped lead a data-driven campaign to persuade the government to drop the one-child policy. "This earthquake is happening and most people don't see it. We feel we have the knowledge to detect this and we should tell the public."
Another concern is a surplus of males. Sonograms became more widely available in the 1990s, and some parents who wanted a son aborted their baby if they learned it was a girl.
Though the practice is illegal, statistics make clear that it is widespread. The male-female ratio at birth was 119 males to 100 females in 2009, compared with a global average of 107 to 100.
Experts fear that, in the years to come, the gender imbalance will create a frustrated generation of men unable to find spouses. That in turn could fuel the trafficking of women and girls to be sold as brides.
Still, not all experts agree the one-child rule should be dropped.
Li Xiaoping, a researcher at the Chinese Academy of Social Sciences, welcomes the coming population decline, saying it will ease food and water shortages and limit pollution. Writing in the state-run China Daily newspaper, Li said the government should stand firm on the one-child limit while finding ways to boost the earning power of a smaller work force.
A change would mark a turnaround from a 30-year-old policy that dates from an era when the Communist Party controlled every aspect of peoples' lives: where they lived and worked, who and when they married and how many children they could have.
The government credits the rule with raising millions out of poverty by preventing 400 million additional births. The gains have come at a cost, however. Families who violated the one-child rule were fined. Some lost their jobs or homes.
Others underwent forced abortions or sterilizations, the subject of well-known author Mo Yan's latest book, "Frog," the tale of a rural midwife who struggles with an emotional breakdown after a 30-year career performing such brutal procedures.
"Yes, our slowed population growth delivered economic prosperity, but needless to say, we've paid a great price," said Mo, whose book was inspired by his aunt, a country doctor. "No matter how you look at it, it's been a tragedy."
Xie Zhenming, who heads the government-funded, research-oriented China Population Association, expects change within the next five years, gradually, in steps.
Susan Greenhalgh, an expert on the policy's history, agrees. The anthropology professor at the University of California, Irvine, believes the government will avoid dramatic change, out of fear that it could revive bad memories and make people wonder whether such a harsh measure was ever necessary.
"My view is that it will gradually be taken apart, piece by piece, over the next few years," she said, "until we all wake up and discover that, lo and behold, the one-child policy has been dismantled to the point that it's no longer a one-child policy."