Health officials are urging parents to put an emphasis on sex education, especially during the summer vacation when the city's unexpected pregnancy hotline usually receives 15 to 20 percent more phone calls.

Shanghai statistics show nearly 63 percent of parents received little, if any, sex education themselves.

More than 15 percent of them never discussed sex-related topics with their teenage children and 27 percent did not know whether their children had a boyfriend or girlfriend, a survey polling 530 parents of children in middle schools revealed yesterday.

Officials said modern and proper sex education from parents were keys to ensuring children's sex safety.

"An improper or rude attitude can push children to extremes," said Dr Zhang Zhengrong from No. 411 Navy Hospital which runs the hotline and offers help for girls and young women.

The survey was carried out by the hotline, 6587-6866, and the education center under the Shanghai Population and Family Planning Committee.

"I have been told many times by patients that they will jump off a building if we tell their parents about the pregnancy," Zhang said.

Since being set up four years ago, the hotline has received about 39,000 phone calls. It has provided around 2,600 discounted medical services for minors and those with financial difficulties.

"We usually provide 20 percent more medical services in and shortly after the summer vacation," Zhang said. "Many girls said they had affairs with Netizens and came to hospital alone without knowing the guy's real name."

The hotline received calls from about 50 pregnant girls and young women in March, April and May and referred them to the hospital.

About 42 percent were three months' pregnant, requiring abortion. About 3.2 percent were too advanced to receive abortions.

Their average age was 18.59 and 74.1 percent were under 18. More than half came to the hospital with their boyfriends but only 9.4 percent had family members with them.