Nearly every working day, Dr. Elizabeth Poynor encounters anxious young women who come to her New York City office with an HPV diagnosis. The human papillomavirus is the most prevalent sexually transmitted diseases - so common that researchers estimate most people will have some form of it in their lifetime. Young adults are especially at risk because they tend to be the most sexually active group.

Dr. Elizabeth Poyner, a gynecological oncologist in private practice, poses for a portrait in her office Wednesday, March 14, 2007, in New York. [AP]

And yet Poynor finds that most of her young patients - even if they've heard of a new vaccine aimed at preventing the worst kinds of HPV - know little about the virus and the harm it can do.

Many women find themselves scrambling to understand HPV after a routine Pap smear determines they have it. And that, Poynor and others say, creates angst that could be avoided with more education.

"This is a very common problem, period," Poynor, a gynecological oncologist in private practice, says of HPV. "That's the first thing I try to tell my patients, to put their minds at ease and to potentially take away some of the stigma that a sexually transmitted disease might carry."

The reasons that HPV is so little known are many. Poynor thinks it's been overshadowed by higher-profile STDs, such as HIV and herpes. Others note that, when marketing its vaccine, pharmaceutical company Merck & Co. has chosen to focus on the potential for cervical cancer rather than the virus itself, which also can cause genital warts.

And then there's the gender divide. Both men and women can have high-risk HPV and low-risk types. But, doctors say, high-risk strains pose more problems for women, potentially leading not only to cervical cancer but also to infertility.

Frequently, men are seen as the silent carriers who can unknowingly spread HPV to their sexual partners. And even when people know they have HPV, they often think condoms offer 100 percent protection, when research has shown that they don't.

That was the case for one 24-year-old woman in San Francisco, who recently learned she has one of the high-risk types of HPV. She was one of a few young women with HPV interviewed for this story, all of whom spoke on the condition of anonymity because of the stigma of having an STD.

"I was scared, sad, disappointed and definitely ashamed. It seemed unfair that I should have it when I've had relatively few partners," says the young woman, who's been sexually active for eight years and had four monogamous sexual partners, including her current boyfriend of two years.

She knew little about HPV at the time. But when her doctor uttered the words "pre-cancer," in reference to the abnormal cells found in her cervix, she frantically searched the Internet to educate herself.

"It definitely made me question a lot about my past choices," says the young woman, who plans to soon attend graduate school to study culinary arts.

Certainly, doctors say, having more sexual partners increases a person's chance of contracting HPV. But, they say, HPV also can be contracted from just one partner and even one sexual encounter.

Having a partner get tested for STDs also isn't a guarantee, as one 22-year-old woman discovered.

"I always made getting tested a requirement. Then I would know I wasn't getting anything," says the recent college graduate who lives in Washington Township, Mich., near Detroit.

She has since been diagnosed with HPV and will soon undergo a procedure known as laser ablation to remove precancerous cells in her cervix. Other procedures often include a colposcopy, which is a close examination of abnormal cells in the cervix, and, if need be, a biopsy in which doctors remove a cone-shaped portion of the cervix to test it.

"I've been in to see the doctor five times in the last month - it's just overwhelming," says the young woman, who ended up sharing her diagnosis with her boyfriend and parents.

Having more information and the support of loved ones has helped.

"When you just say STD, people are like 'Ohhh,'" she says. "But when you ask those questions and understand more about it, it's not necessarily as scary."

While some women who have HPV think it's too late for them to be vaccinated against HPV, some doctors say it would still be worth it, since it shields against the worst four types of HPV.

"Even if a young woman has one type of high-risk HPV, there's nothing to say that she cannot be infected with the other three," says Dr. Tina Tan, an infectious disease specialist at Children's Memorial Hospital in Chicago.

Federal officials recently recommended that girls as young as age 9 receive the HPV vaccine. Some parents remain reluctant, though - worried that the vaccine could be considered a license to have sex.

Dr. Gary Rose, head of the Medical Institute for Sexual Health in Austin, Texas, says parents should reconsider, even if they're certain their daughters will wait until marriage for sex.

"There are a couple of things you can't be sure of," he tells those parents. "One is the sexual history of the person your daughter marries." The other, he says, is the risk of abuse or rape.

Because the vaccine does not protect against all types of HPV, Poynor and Tan say regular Pap smears and early treatment remain keys to fighting the virus. And they agree that some protection from condoms is better than none.

One young woman from San Antonio, Texas, who was diagnosed with HPV two years ago, also calls educating men about their role in spreading HPV "crucial."

"I had to tell my boyfriend about it," says the 26-year-old professional, "and he still doesn't get what it is."