Song Xingrong, director of the anesthesia department at Guangzhou Women and Children's Medical Center, said natural childbirth may bring the most acute pain a Chinese woman will experience in life.

Most births in China are natural - with no pain intervention - or C-sections, which are generally painless because of techniques such as epidural and spinal anesthesia.

Pain-free vaginal deliveries, which may rely on a combination of spinal and local anesthesia, account for less than 5 percent of all deliveries in China. In Guangdong province they account for about 10 percent of deliveries, Song said.

Painless labor - a vaginal delivery aided by an epidural or spinal painkiller - is safe for both mother and child, he said.

"A major factor that discourages hospitals from providing painless labor is that it is not covered by basic medical insurance programs in China," he said.

"Many people in China have not heard of painless vaginal labor because of lack of promotion. Only 20 percent of pregnant women who come to our hospital are aware of it," he said.

In the United States, 85 percent of vaginal births are painfree, Song said. In Beijing, it's less than 30 percent, he said.

Yue Hongli, an anesthesiologist at Beijing Tiantan Hospital, said not all pregnant women are good candidates for pain-free labor, including those with serious lung or heart disease, or who cannot give birth naturally - in which case a C-section is required.