Oldest Profession Flourishes in China

"They are absolutely moral. A lot of these women send half their income back to support their families. They're more filial than I am," Jing said. "Among government officials, Chinese social scientists, health professionals, they are coming around to see that prostitution is not fundamentally connected to a lack of values but a lack of jobs, choices, opportunities and education."

And as the growing number of sex workers forces the price of sex to plummet, health workers are also concerned about a rise in medical risks.

"The impact is very simple. Sometimes a sex transaction is only 10 yuan [$1.33] in Sichuan province, under a bridge or an overpass," Jing said.

Jing said about 40 percent of the female sex workers tested by China's Center for Disease Control and Prevention two years ago were older than 35. "Among sex workers infected with HIV-AIDS, 60 percent are older than 35. That means there are some really desperate women," Jing said. "The lower you go in price and quality of the sex workplace, the lower the rate of condom use."

There were 174,506 reported syphilis patients in China last year, up 31 percent from 2005, said Wang Quanpei, a Nanjing-based researcher with China's CDC. But because many people with sexually transmitted diseases visit unregistered doctors, and partly because many hospitals specializing in these diseases are badly managed, the actual number of infected patients is estimated to be as much as 10 times higher than reported, experts said.

AIDS education in China is inadequate, and awareness of STDs remains poor, surveys show. Increasingly fierce competition among prostitutes means that often-ignorant customers have growing leverage over prostitutes who feel disadvantaged.

In a karaoke bar in northern Beijing, for instance, a 37-year-old prostitute from Hubei province said her main goal was saving enough money to support and win custody of her 9-year-old son, who lives with an estranged and abusive husband.

"If I was still with my ex-husband, he would have chopped me into pieces if he knew what I did for a living," said the woman, who asked to be identified only by her last name, Wang. "There are other ways to do business, but I need the money. Old women like us can't make a lot of money here."

She doesn't visit a gynecologist very often, because she doesn't believe she is sick. And each week, Wang watches the more cautious sex workers in the bar lose clients to other prostitutes.

"Another girl named Lily was abandoned by a customer named Big Brother Yao because she refused to have sex without using a condom," Wang said. "He's a frequent visitor here, and he's famous for not using a condom. He never called her again. She lost that business forever."

When Wang's customers insist on not wearing a condom, she usually gives in. She feels safe because she doesn't have sex with customers "very often," she said. "Who said that you will be infected as soon as you have sex with your customer?"

Her clients would probably agree. Most men who seek out prostitutes think sexually transmitted diseases are no more serious than a cold and are easily cured, according to preliminary results from a 2006 survey by the Institute for Research on Sexuality and Gender at People's (Renmin) University.

These days, prostitution is becoming less of an organized business and more of an exercise in individual entrepreneurship. Mid-level sex workers with a few years of experience are striking out on their own in residential compounds, renting apartments and finding their own customers, "because it's safer than a club or bar that's exposed to a police raid," said sexologist Pan Suiming, who heads the institute, referring to the occasional official efforts to crack down on the trade. "Competition is fierce."

Male prostitutes, whose prices have also been affected, say their customers are no longer just bored or lonely middle-age women but mostly a growing number of female sex workers who hire them in order to erase the sting of being used themselves.

The 22-year-old freelance prostitute tells her family she works in a supermarket. Armed with an elementary school education and a short stint as a textile factory worker, her only other job before becoming a sex worker was washing dishes 12 hours a day in a hotel in Shandong.

"There was a karaoke parlor in that hotel, and all the girls there didn't have to work at all, yet they made big money! I worked all day but only got 400 yuan [$53] a month," she said. "It's all because of money that I became 'bad' and joined this business."

News researcher Jin Ling contributed to this report.