Hubei University sophomore Song Zhenhua's husband carries her out of a dormitory to their wedding in 2012. [CHEN YONG/CHINA DAILY]

Minority group

Although the ban was lifted, undergraduates' willingness to marry has not changed much in the past 10 years.

A survey conducted in 2012 on Renren.com, a social networking website popular among college students, showed that only 17 percent of such students said they were willing to marry whilst at university.

Lao said he received wedding invitations from some of his graduate students in the past 10 years, but none from his undergraduate students. "Only a minority of undergraduates are getting married at university in China," he said.

Zhou Xiaopeng, director of the Marriage Research Institute under Baihe.com, a dating website, said most undergraduates get married on the spur of the moment.

"As young people, they are keen to make promises, and a key way of doing that is to get married."

Fan said her marriage was, to some extent, the product of a sudden impulse.

"When I had to leave Sao Paulo in 2013, I couldn't bear to be separated from my boyfriend. I wanted to stay with him forever, so I married him," she said.

Some students get married because of unexpected pregnancies.

A 23-year-old woman in Chongqing, who declined to give her name, is one example. She married her boyfriend, also her middle school classmate, in November last year, when she was a senior student at a local university.

"We had been in love for years and had planned to register for marriage after I graduated from university in June this year," she said.

"We finally had to marry earlier because I conceived. We want the baby to have a complete family when he or she is born."