China's lawmakers resumed on Tuesday a controversial debate on the criminalization of sex identification of embryos for pregnant women.

A Chinese father carries his child at a park in Shanghai on September 8th. Urban couples generally feel ease at their babies' sex while most in the vast countryside favor boys. [AP]

The provision in the draft Sixth Amendment of the Criminal Code has been proposed as a way to prevent the marked imbalance in births towards boys.

However, the Standing Committee of the National People's Congress (NPC) was sharply divided when the issue came up in the first of three legislative reviews last December.

Members heard in the second review Tuesday that the draft law provides penalties of up to three years in jail, probation and fines for those involved in gender identification of embryos for non-medical purposes.

A Standing Committee official said that some members considered the provision necessary to curb the country's abnormal sex ratio and prevent the use of abortion as a means of sex selection.

Opponents maintained the law was unreasonable and impossible to police as evidence of the proposed crime would be hard to collect, and it was difficult to judge if an abortion had resulted from sex identification.

Considering the significant differences, the NPC Law Committee had left the provision unchanged and the draft amendment had been submitted to the Standing Committee for further review, he said.

Statistics from the State Family Planning Commission show 117 boys born for every 100 girls in China, well above the international average of 104 to 107 boys.