People in Shanghai are reluctant to have more than one child as the cost of raising children, house prices and the cost of education are their top three concerns, according to a survey released by the Shanghai Health Commission and the Shanghai Academy of Social Sciences at a seminar on Sunday.

The gathering was to promote fertility protection ahead of World Contraception Day on Monday.

Out of the 19,314 women aged between 20 and 49 living in Shanghai covered by the survey, only 13 percent of those with their households registered in Shanghai have given birth to a second or third child.

The survey also showed that those who have a larger house are more willing to have more children. Those with an annual family income of less than 100,000 yuan ($14,000) registered the lowest willingness to have children.

"It is necessary to improve relevant policies on housing and education, and increase financial input to alleviate the burden of child rearing," said Zhou Haiwang, a researcher at the Institute of Urban and Population Development Studies at the Shanghai Academy of Social Sciences at the seminar.

According to official data, Shanghai registered a fertility rate of 0.7 in 2021, far below the national average of 1.15.

Late marriage and increased infertility brought about by induced abortions are also major factors contributing to the low fertility level in big cities, said experts attending the seminar.

Professor Cheng Linan, an honorary academician of the Royal College of Obstetricians and Gynaecologists, and Chen Rong, an associate researcher of the Asian Population Research Center and Population Research Institute of Shanghai University, pointed out that the trend of young people delaying marriage is obvious.

In China, where childbirth in marriage is still the norm, late marriage leads to postponement of the first childbirth, hence reducing the probability of having children, they said.

In contrast, the abortion rate is going up. According to data released by the National Bureau of Statistics, while the national number of births in 2021 was 10.62 million, that for abortions stood at more than 9 million in the same period. The proportion of women under the age of 25 who've had an abortion was 47.5 percent, and the proportion of these women who had never had children was 49.7 percent.

"Adolescents have become one of the main groups having abortions. Unmarried adolescent women have nearly 4 million abortions every year, accounting for 40 percent of the total number of abortions in China, of which 19 percent have multiple abortions," said Wang Peian, executive vice-president of the China Family Planning Association.

Experts believe a lack of formal sex education is partly to blame, referring to some surveys of Chinese college students, which revealed only half of the respondents had received formal sex education.

"Schools and society have the responsibility and obligation to carry out popular science education on reproductive health to teenagers, and raise their awareness of protecting fertility," said Yan Hongli, a healthcare professional.

Clinical evidence proves that multiple abortions have a greater impact on women's fertility, which is also one of the main reasons for the increase in the incidence of infertility in China, said He Xiaoying, deputy chief physician of the Family Planning Department of Shanghai First Maternal and Child Health Hospital.

Zheng Zheng contributed to this story.