"Many women turn to their obstetricians or psychologists for advice, only to be told, 'Share your feelings with your husband more' or even, 'Don't think about it too much. Marriage is about companionship,'" he said.

Faced with a dearth of solutions, some women are searching for answers elsewhere. In 2012, the association interviewed women in beauty salons and massage parlors and discovered that many were happy to unburden themselves and discuss their problems with members of staff.

"The circumstances relaxed them and they found it easier to open up. Psychosexual problems are not the sort of illnesses that should be always cured in the hospital with busy, serious physicians," Ma said.

In 2010, the association attempted to persuade the Ministry of Human Resources to list sex therapist and sex consultant as regular jobs, but the request was turned down. "They said that only trained physicians can be given that job title," he said. "But in other countries, such as the UK and the US, sex therapists gain certification through the colleges and schools in which they train, or through national associations."

Conventional measures

Chen said his wife's lack of interest in sex led him to look for other ways to obtain the satisfaction he craved. In the past seven years, he has had seven different sexual partners, all but one of them married or in a long-term relationship. The exception was a woman in her 20s, who wanted to lose her virginity to an experienced man so she would have a "less painful first time".

One of Chen's partners refused to sleep with her husband to punish him for having a string of affairs during her pregnancy. "She had the desire for sex but couldn't accept her husband. However, by having sex with me, she settled the score between them and she was able to have sex with her husband again," he said.

He said the relationships have no emotional element, but are simply about sex. "It benefits both of our families. We are more tolerant to our partners and are sexually satisfied. I even think I'm almost a sex therapist now," he said.

However, Shang Dalei, a socio-philosopher, said affairs like those in which Chen engages erode values and the resolution of psychosexual problems should be left to the professionals.

"The more tolerance he (Chen) gains for his sex life outside marriage, the more he will lose faith in marriage and his basic commitment to his wife will falter," said Shang.

Related: On the couch

To regulate the profession and improve people's sex lives, Ma Xiao-nian said his association will standardize training courses for therapists and consultants in March. The courses will be aimed at psychologists and physicians, who will be accredited by the association if they pass the course exam.

"That's good news for people with psychosexual problems. They can turn to professional therapists instead of massage girls," said Ma, the therapist in Shanghai. "Moreover, it may stop frustrated men from visiting prostitutes or having casual sex outside marriage."

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