WEDNESDAY, July 21 (HealthDay News) -- Many women who've had a Cesarean section may be candidates for vaginal birth in future pregnancies, say new guidelines from the American College of Obstetricians and Gynecologists.

"These guidelines emphasize again that a trial of labor after Cesarean is an important option for most women," said one of the authors of the new guidelines, Dr. Jeffrey Ecker, a maternal-fetal medicine specialist at Massachusetts General Hospital in Boston.

Years ago, experts believed that once a woman had undergone a Cesarean birth, she would have to deliver any subsequent pregnancies with a C-section as well. But with changes in surgical procedures and growing evidence to support the possibility of a vaginal birth after a Cesarean (VBAC), attitudes began to shift.

However, in the 1980s and 1990s, as the VBAC rate increased, so did complications related to the procedure. Because of concern over complications and possible legal consequences, the VBAC rate dropped dramatically, from 28.3 percent of deliveries in 1996 to 8.5 percent in 2006. But repeat C-sections also have a risk of complications for mother and baby, the authors of the guidelines noted.

Currently, almost one in three mothers delivers by Cesarean in the United States, according to the study.

More recent studies have supported the idea that many women can successfully deliver vaginally after having had a Cesarean, explained Dr. William Grobman, another author of the new guidelines and an associate professor of obstetrics and gynecology at Northwestern University's Feinberg School of Medicine in Chicago. In March, a National Institutes of Health panel came to the same conclusion and said that a Cesarean delivery in the past doesn't mean a woman must automatically have one in subsequent pregnancies.

The new guidelines recommend counseling women who've had one Cesarean birth using a horizontal incision low in the uterus (low transverse incision) that they are candidates for VBAC, and offering the option of a trial of labor so they can attempt to deliver vaginally.

Between 60 percent and 80 percent of women who attempt VBAC have a successful vaginal delivery, according to the guidelines. Grobman said those numbers are population-based numbers and that for some women, the success rates may be much higher.

The guidelines, published in the August issue of Obstetrics and Gynecology, suggest that the following women may also be candidates for a trial of labor after a Cesarean:

• Women who've had two previous C-sections using a low transverse incision.
• Women who've had a C-section with a low transverse incision who are currently pregnant with twins.
• Women who've had a Cesarean delivery but don't know if they had a low transverse incision.

Some women definitely aren't candidates for VBAC. These include women who've had a vertical incision on the uterus or serious pregnancy complications, such as placenta previa, said Grobman.

"For some women, a VBAC remains an inappropriate choice. But for many, if not most women, choosing a trial of labor when you've had a C-section is an appropriate choice," said Ecker.

The guideline authors hope that women and their health care providers will feel a "sense of shared decision-making," Grobman said. "Rather than provide a directive of 'you can' or 'you can't' do this, doctors need to provide information about the potential risks and successes and let women have autonomy to make their own decision."

Dr. Peter Bernstein, a professor of clinical obstetrics, gynecology and women's health at the Montefiore Medical Center in New York City, said he's very pleased to see the new guidelines.

"Over the last 10 years or so, the pendulum has been swinging too far away from VBAC, and I think they're trying to swing the pendulum back the other way to a more reasonable position and making it available to women who are interested in it," he said.

More information

To learn more about vaginal birth after a Cesarean delivery, see the National Institutes of Health.

TUESDAY, July 20 (HealthDay News) -- A new study finds that the human papillomavirus (HPV) vaccine protects not only against the sexually transmitted virus that causes cervical cancer, but also helps prevent genital warts and low-grade cervical growths.

The findings are published in the July 21 online edition of BMJ. Health officials in the United States have been urging vaccination of young women and girls.

The researchers estimate that the virus causes an estimated 500,000 cases of cervical cancer in women each year around the world. The virus can also cause warts in the genital area and low-grade cervical growths. Those two conditions are thought to strike 30 million people annually.

In the just-released randomized control trial, researchers studied 17,622 women in 24 countries and territories who had been assigned to take the vaccine or a placebo over a six-month period. The women were aged 16 to 26.

Joakim Dillner, of the department of medical microbiology, Lund University, Malmo University in Sweden, and colleagues found that the vaccine provided significant protection against the warts and tumors in susceptible women. For example, 168 of 7,632 women who took the placebo developed cervical growths attributed to HPV strains, while just seven of the 7,629 who took the vaccine did, they noted.

In the big picture, the study authors wrote, the vaccine "provided strong and sustained protection" for four years against various types of warts and low-grade female genital growths.

The study was funded by Merck Research Laboratories, a division of Merck & Company, maker of the HPV vaccine Gardasil.

Dr. Clyde Crumpacker, a professor of medicine at Harvard Medical School in Boston, said in an interview that the study is useful because it shows the vaccine can do more than prevent the virus from spreading.

"The vaccine has not yet been licensed for boys, but this study provides a strong case that boys should be vaccinated to prevent acquisition of HPV and prevent genital warts," said Crumpacker.

More information

The U.S. National Library of Medicine has more on HPV.

SUNDAY, July 18 (HealthDay News) - Effective and widespread treatment of HIV disease may also help cut the rate of new infections, researchers report.

Since the introduction of powerful anti-HIV drugs known as highly active antiretroviral therapy (HAART) in 1996, the number of new cases of HIV infection in the Canadian province of British Columbia has decreased by more than half, the team report.

The study is published online July 18 in The Lancet in conjunction with its presentation Sunday at the International AIDS Society (IAS) meeting in Vienna.

"Our results show a strong and significant association between increased HAART coverage, reduce community viral load, and decreased number of new HIV diagnoses per year in the population of a Canadian province," Professor Julio Montaner, director of the British Columbia Centre for Excellence in HIV/AIDS, and his colleagues wrote in a news release issued by the journal.

HAART slows the progression of HIV/AIDS symptoms.

The team analyzed data from the British Columbia Centre for Disease Control and found that between 1996 and 2009, the number of people receiving HAART increased from 837 to 5,413 (547 percent increase) and the number of new HIV diagnoses fell from 702 to 338 per year (52 percent decrease).

For every 100 additional patients on HAART, the number of new HIV cases decreased by 3 percent. There was also a significant decrease in mean HIV viral load concentrations, a trend linked to the decrease in new HIV cases, the researchers said.

New HIV diagnoses fell by 30 percent between 1996 and 2000, declined 2 percent between 2001 and 2003, and fell another 17 percent between 2004 and 2009. Evolving treatment guidelines led to substantial increases in HAART use in 1996-2000 and 2004-09, the study found.

The largest decrease (nearly 50 percent) in new HIV cases between 1996 and 2009 was among injection drug users.

The researchers also found that rates of sexually transmitted diseases and hepatitis C infections increased during the last years of the study, which suggests that the decrease in new HIV cases can't be attributed to a decrease in risky sexual behaviors associated with HIV transmission.

"Our results support the proposed secondary benefit of HAART used within existing medical guidelines to reduce HIV transmission [and] provide a strong rationale for re-examination of the HIV prevention and treatment dichotomy, as has been strongly advocated by the UN Joint Program on HIV/AIDS (UNAIDS) as part of a comprehensive combination prevention strategy," the researchers concluded.

This study, as well as previous work by Montaner and his colleagues, have helped shape the new UNAIDS strategy that calls for 15 million HIV patients worldwide to be treated with antiretroviral drugs, instead of the current five million patients. The plan would cost $26 billion a year.

HIV/AIDS experts should take note of the Canadian researchers' study, two Italian doctors wrote in an accompanying editorial in the journal.

"While waiting for an effective vaccine, experiences such as those reported today should be strongly considered by clinicians, national and international agencies, policy makers, and all parties involved in the development of treatment guidelines, because the population-based dimension of HAART might play an important part in the future control of the HIV epidemic," wrote Dr. Franco Maggiolo and Dr. Sebastiano Leone, Division of Infectious Diseases, Ospedali Riuniti in Bergamo.

More information

The New Mexico AIDS Education and Training Center has more about antiretroviral therapy  .

MONDAY, July 19 (HealthDay News) -- A vaginal gel applied consistently before and after sex reduced the risk of HIV infection by more than half, according to a study presented Monday at the International AIDS Conference in Vienna.

The gel contains tenofovir (Viread), an antiretroviral drug used to treat HIV/AIDS.

"If this was implemented and women in the general population used it in the same way as we observed in the trial, it could avert 1.3 million infections over the next 20 years," said study co-author Dr. Salim S. Abdool Karim. The report also appears in the July 20 online issue of Science.

Despite these promising results, the gel still needs to be further researched, licensed and approved and is not likely to be available to women at clinics any time within the next year or two, said Abdool Karim, who is director of the Centre for the AIDS Programme of Research in South Africa (CAPRISA) and pro vice-chancellor (research) at the University of KwaZulu-Natal in South Africa.

U.S. health officials quickly applauded the findings.

"The CAPRISA microbicide trial results are an exciting step forward for HIV prevention. While these findings may need to be confirmed by other research to meet requirements for licensure by [the U.S. Food and Drug Administration] and other regulatory bodies throughout the world, they suggest that we could soon have a new method to help reduce the heavy toll of HIV among women around the world," Dr. Kevin Fenton, director of the National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention at the U.S. Centers for Disease Control and Prevention, said in a CDC statement.

"Women represent the majority of new HIV infections globally, and urgently need methods they can control to protect themselves from infection. It is also very encouraging that the study found that the microbicide significantly reduced the risk of genital herpes [HSV-2], which is common in developing countries and in the United States, and facilitates HIV transmission," Fenton added.

Almost three-quarters of AIDS cases worldwide are in Africa, especially sub-Saharan Africa. Women represent about half of all HIV infections globally; young women are particularly at risk.

So far, trials of microbicides -- compounds to be applied to the vagina or rectum to prevent infection with sexually transmitted diseases (STDs) -- have been disappointing.

Eleven trials in the past 15 years have shown no change or even sometimes an increase in transmission rates, said study co-author Quarraisha Abdool Karim, associate director of CAPRISA and an associate professor of epidemiology at the Columbia University Mailman School of Public Health in New York City.

Quarraisha Abdool Karim and Salim S. Abdool Karim are married.

For this study, close to 900 HIV-negative women aged 18 to 40 in urban and rural KwaZulu-Natal, South Africa, an epicenter of the AIDS epidemic, were randomized to take the Viread gel or a placebo gel.

Participants were told to administer two doses of the gel: one within 12 hours before sex and one within 12 hours after sex.

The trial lasted almost three years.

Overall, the gel reduced HIV infection by 39 percent. But in women who had high adherence (using the gel more than 80 percent of the time), the risk reduction was 54 percent, compared to women in the placebo group.

"Without this gel, for every 100 women we may see 10 women being infected in a year," said Salim S. Abdool Karim. "With this gel, we would see only six women being infected."

The gel also reduced the risk of contracting genital herpes by 51 percent, a factor which could slow the spread of HIV even further, given that people with genital herpes have double the risk of getting HIV, said Salim S. Abdool Karim.

The gel appeared to be less effective after 18 months. "We think the diminishing protection is largely due to diminished adherence," said Salim S. Abdool Karim, although this is not proven.

"I think one of the differences is that all the other products were surface-active. They needed to be on the surface of the vagina sufficiently available and sufficiently well-spread in order to prevent HIV infection," said Salim S. Abdool Karim. "Tenofovir is not surface-active. It goes into cells which HIV will be targeting so it acts at a different point in the pathogenesis process."

In their quest to get the gel on the market and widely used, the researchers will be enlisting the help of marketers.

"This is simply a cylindrical white plastic tube. You can't get anything more unattractive," said Salim S. Abdool Karim. "Even Coke would have gone bankrupt if they had adopted this approach to their marketing. We only made this gel for the study. I think the future is going to involve making this gel sexy, making this gel something that is part-and-parcel of the sex act, that enhances sex. Packaging is part-and-parcel of addressing the adherence issue."

More information

The U.S. Centers for Disease Control and Prevention has more on HIV/AIDS.