A report published in the New England Journal of Medicine in the United States makes the case that China's family-planning regulation is out of date 25 years after the country implemented its one-child policy.
The policy aimed to slow the birth rate in the world's most populous country, and the government claims it has helped China's rapid economic growth. But as living standards improve, surveys say many parents would welcome a relaxation of the policy.
Critics also say the side effects of the policy pose serious problems for the country.
Critics, however, say the strict policy has led to many social problems. Forced sterilization and abortions are commonplace, especially in rural areas, where local Communist Party officials take extreme measures to meet mandated population targets.
A growing problem is sex-selective abortion. Traditionally in China, sons are preferred over daughters. Because of the one-child policy, many pregnant women have abortions if tests show they are having a girl. Worse, some baby girls receive such poor care they die, or they are abandoned.
Government statistics say that there are 117 baby boys in China for every 100 girls. Experts worry that this could have dangerous social consequences, when those baby boys grow up and have no hope of marrying.
Despite these problems and fresh criticism, experts believe China is unlikely to change the one-child policy anytime soon. China says it has a population of 1.3 billion, and the government wants to make sure it is below 1.4 billion in 2010. Beijing leaders think any changes that would compromise this goal might threaten economic growth and stability.
But the authors of the critical study say the country's economic growth probably means the policy no longer is needed. In a trend seen in other countries in Asia over the past decades, as China's economy improves, most couples voluntarily opt to have fewer children.
The Chinese government has begun offering economic incentives to families with fewer children in poverty-stricken areas. It also initiated a campaign called "caring for girls" to promote gender equality and eliminate discrimination against girls - aimed at correcting the gender imbalance, while still adhering to the population policy.