Image caption Jocelyn and Jun have been married for nine years

"From the first time I started to love a Chinese man, hiding became part of my life," says American Jocelyn Eikenburg.

She had moved to Shanghai in 2003 to be with her now-husband Jun Yu.

"In the past, students had been expelled for dating or marrying foreigners. We didn't know what would happen if the university administration found out, so we told no-one he was living off-campus with me," she says.

A foreign woman with a Chinese man is a rare pairing.

Within her small expat community the social isolation was almost immediate. She felt alienated by her girlfriends, who would openly express their distaste for Chinese men.

"I felt alone in being married to a Chinese man and I wanted to find other people to connect with," says Ms Eikenburg about her decision in 2009 to share her experiences on her blog, Speaking of China.

She says she now receives scores of emails a month from Chinese people curious about meeting and dating foreigners, or partners new to, or experiencing difficulties, in cross-cultural relationships.

'The Legend'

In 1978, there was not a single inter-racial marriage registered in mainland China, according to government figures.

But the numbers of Chinese marrying foreigners has gradually risen, with 53,000 such couples tying the knot in 2012.

Jun's parents married in 1971 during Mao Zedong's Cultural Revolution (1966-76), when China was closed to the world.

It was a time when public displays of affection were punished and any discussion of sex was considered Western spiritual pollution.

To his parents' generation it was inconceivable to marry a foreigner.

But that all changed with reform and China's "opening up", says Richard Burger, former editor of a state-run newspaper in Beijing and author of Behind The Red Door: Sex in China.

A sexual revolution has taken place in China; from the way people are dressing, couples holding hands in the streets in main cities, and young people becoming less inhibited about sex.

A factor in this revolution is that young Chinese people increasingly have greater autonomy from their parents in choosing a partner, Mr Burger says.

"For me to date and marry a Western woman was rebellious in a sense," says Jun, recalling that his father had cautioned him that foreigners could be friends but never lovers or wives.

Image caption China has become more open to Western influences

More often than not Chinese families are wary or disappointed by such unions, but Jun says he was fortunate that as the youngest of three brothers his parents were more permissive.

By contrast, Jun is known as "the legend" amongst his peers as they generally regard having a Western wife as a "status symbol", he says.

But when it comes to cross-cultural marriage, far more Chinese women date or marry Western men than the other way around.

One of China's most famous scholars of sex, Li Yinhe, says one possibility is that Chinese men lack confidence.

Mr Burger agrees saying: "Men are engrained with a cultural imprint and are brought up to believe that they are the head of the household, they have the power.

"It is very intimidating approaching a Western woman, who has a perceived higher level of education, more money or earning power, and greater sexual experience."

'Western fantasy'

China's 'leftover' women "Leftover women" (sheng nu) is used widely in China to refer to unmarried women over 27

It has been used in state-run media and by some state bodies since 2007

The website of the state's supposedly feminist All-China Women's Federation featured articles about "leftover women" - until enough women complained

It is in China's big cities that the surge in inter-racial relationships is most apparent.

When Yue Xu, an actress and self-styled dating guru, returned to her native Beijing in 2012 after years living in the US, she was struck by the increase in expats in the capital, and the number of Western men dating Chinese women.

"In the West, Asian women are portrayed as exotic beauties; a librarian in public but kinky in the bedroom. In China, the Western fantasy meets reality," she says.

"Chinese women are brought up to be the care takers - they know how to look after their men. But in most households it's the woman who makes all the major financial decisions."

Yue says that in general Chinese women have become far more aggressive when it comes to dating, something she attributes to social pressure and the fear of being labelled a "left-over woman" at 27.

China's 'bare branches' In China, 118 boys are now being born for every 100 girls

By the end of this decade the country will have 24 million "leftover men" of marriageable age

Between 2020 and 2050, some scholars estimate that 15% of Chinese men will not find a wife

But she says the media - movies, television shows, online dating sites - also play a role.

"There is a mindset 'If I'm going to find love, I need to find it myself. No-one else can do it for me'," she says.

A number of high-profile mixed couples have captured headlines in China and the West, perhaps driving the trend.

Wendi Deng, who became known as the 'tiger wife', was married to media tycoon Rupert Murdoch for 14 years before their split in June.

Earlier this year, British actor Hugh Grant announced the birth of his second child with Chinese partner Tinglan Hong.

The West captured the imagination of Yong Zhi as a young girl growing up in Beijing.

She "dreamed of travelling abroad". An "addiction" to Western novels inspired her to study English Literature at the prestigious Jilin University in north-east China.

Image caption Wendi Deng and Rupert Murdoch married in 1999 and have two daughters

"I was dating but half-heartedly. I'd made it clear to my Chinese boyfriend that I wanted to go abroad so there was a limit as to where our relationship could go."

Yong met her husband David within two months of arriving in the UK to study at the University of Liverpool. She is celebrating 16 years of marriage.

She says she knows of educated, good-looking women who go to certain bars in the hope of meeting a Western man to marry.

"They have an image in their head and want to live 'the dream'."

A mixed marriage can offer greater opportunities to travel and educate your children overseas. Being able to speak English elevates you in terms of salary and job opportunities, she says.

But cross-cultural marriage can be tricky, says a relationship counsellor at the non-profit Community Center Shanghai (CCS), who gave her name as Aiching.

When you're in love with someone from another culture, when you treat them as your equal, it's easy to forget that you learned different ways to respond to problems Jocelyn Eikenburg

Life plans, communication, emotional management and acceptance of cultural differences are common issues.

"The couples I have counselled married or dated because they fell in love. But they still have to face the challenges and struggles of daily life.

"I do not focus too much on that they are from different races. People tend to use it as the easiest excuse to give up on trying to help their marriages," she says.

Aiching says she helps couples to talk about their feelings - something which is "kind of taboo" for Chinese - and to understand one another's cultures.

Jocelyn says there was a time in her relationship with Jun when stress, personal issues and cultural differences collided to create a "perfect storm".

"When you're in love with someone from another culture, when you treat them as your equal, it's easy to forget that you learned different ways to respond to problems, and different ways to communicate," she writes in her blog.

"What I've learned is that I can lose my temper if Jun doesn't understand what I'm trying to say - and Jun, on the other hand, can stonewall me at a time when I most need him to talk."

The couple, however, weathered that storm. They plan to live in China permanently and hope to give Jun's parents a longed-for grandchild.