Mothers may play a key role in whether their daughters get the human papillomavirus (HPV) vaccine, even if the daughters have already left the nest.

A new study found college-age women who talked with their mothers about the HPV vaccine were nine times more likely to get it than those who did not discuss it.

"It is an encouraging finding, because it shows that communication between mothers and daughters can be very helpful, even if it may be difficult sometimes," said study researcher Janice Krieger, an assistant professor of communication at Ohio State University.

However, researchers noted that the study was small and focused on students at one particular university, so its findings might not be representative of the population as a whole.

Many mothers and daughters may be uncomfortable talking about the HPV vaccine because it is designed to prevent the spread of a sexually transmitted virus, Krieger said.

But getting the three-shot vaccination series is important because a persistent HPV infection may cause cervical cancer, the researchers said. The Centers for Disease Control and Prevention recommends that girls and women ages 11 to 26 receive the vaccine. HPV is the most common sexually transmitted infection, and will infect about half of sexually active people in the United States during their lifetimes.

Two vaccines are currently approved by the Food and Drug Administration to protect girls and women against HPV: Gardasil, manufactured by Merck & Co., and Cervarix, manufactured by GlaxoSmithKline. The study involved 182 mother-daughter pairs. All of the daughters were Ohio State students, and their average age was 20.

The daughters mailed a questionnaire about the HPV vaccine to their mothers and completed a similar questionnaire themselves.

Overall, 137 of the mother-daughter pairs said they had talked about the HPV vaccine; the other 45 pairs reporting not discussing the vaccine.

Results showed that daughters who discussed getting the vaccine with their mothers, and those who reported believing that the vaccine was safe and effective in preventing HPV-related diseases, were more likely than the others to get the vaccine .

The researchers also found that fears about susceptibility to HPV and about the severity of HPV-caused illness — on the parts of mothers or daughters — were not related to whether they talked about the issue.

"Fear does not seem to be the motivator," Krieger said.

The data don’t show what the women talked about when they discussed the HPV vaccine, but Krieger said she suspects that one topic was the vaccine's cost, which has been reported to range from $360 to $600 for the series of three shots.

That could be one reason few young women are vaccinated. It also would be one reason why it is important to get mothers involved, even after their daughters reach adulthood, Krieger said.

"Most women in early adulthood don’t have a lot of extra money, and even if they do, a preventive vaccine like the HPV vaccine may not be high on their list of things to buy," She said.

One recent study found that just one-third of teens and young women who start the three-dose vaccine series actually finish, and almost three-quarters don't start it at all.

"Mothers may be afraid to bring up the topic, but it doesn’t have to be a conversation focused on sex. Mothers can talk about how the HPV vaccine is safe and effective, and that it prevents cancer," Krieger said.

The study appears in the January issue of the journal Human Communication Research.

Pass it on: Moms may play an important role in persuading their college-age daughters to get the HPV vaccine.

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