An "adult health" expo in Shanghai was more restrained than previous years in terms of the "suggestiveness" that had drawn repeated protests, local media reported on Friday.

Models at the 2015 China International Adult Toys and Reproductive Health Exhibition, a four-day event that kicked off on Thursday, did not dress as scantily as at previous exhibitions when displaying adult products, while the expo saw fewer visitors than last year, according to Shanghai Morning Post.

A company representative told the newspaper that it had planned to invite five Japanese porn stars to attend, but reduced it to just one.

The Shanghai Morning Post noted that 80 percent of visitors who attend the expo on Thursday were male and the number of visitors had fallen by a third compared to last year. However, the report did not link the decrease of visitors with the lack of explicit performances.

 China has a sharp divide between those eager to embrace sexual openness and those who criticise this as "foreign culture" and claim that such matters should be kept behind closed doors.

Well-known sexologist Peng Xiaohui had human waste thrown at his face by a protestor when he was giving a speech titled "Sex is the basis of happiness" at a sex culture festival in Guangzhou, Guangdong Province in November.