Merck, maker of the cervical cancer vaccine Gardasil, is backing off its lobbying campaign following pressure from medical groups and parents who believe the vaccine should not be mandated as a school attendance requirement for adolescent girls.

The public outcry that caused Merck to announce its stop order on Tuesday stems from the fact that the vaccine protects against the sexually transmitted human papilloma virus (HPV), which causes cervical cancer. School-mandated vaccines are typically for diseases spread through casual contact, such as measles and mumps.

Merck's medical director for vaccines, Dr. Richard M. Haupt says, "We're concerned that our role in supporting school requirements is a distraction from that goal, and as such have suspended our lobbying efforts," adding that the company will continue providing information about the vaccine upon request.

Gardasil, launched in June and the first vaccine to prevent cervical cancer, has inspired controversy since day one. There's the cost -- $360 for three required shots -- and all sorts of insurance concerns and conservative groups who worry the vaccine encourages premarital sex and interferes with parental rights. Even those in support of the vaccine -- like the American Academy of Pediatrics and the American Academy of Family Practitioners -- question Merck's quick push to market this drug, especially in light of the company's withdrawn painkiller Vioxx.

"I believe that their timing was a little bit premature so soon after (Gardasil's) release, before we have a picture of whether there are going to be any untoward side effects," says Dr. Anne Francis, who chairs an American Academy of Pediatrics committee.

Legislatures in 20 states have taken steps to mandate the vaccine for young girls. And with the exception of Texas governor Rick Perry's February 2 executive order requiring Texas girls entering the sixth grade in 2008 get vaccinated, nothing has been made official so far.