African-American, Hispanic and low-income adolescent women are less likely to complete a series of three vaccinations to prevent human papillomavirus (HPV), a diagnosis that carries a higher risk for potentially life-threatening cervical cancer, according to a new study published in the American Journal of Preventive Medicine and reported by the Health Behavior News Service.

HPV is a common sexually transmitted infection that can be spread to both men and women through simple skin-on-skin contact. What’s more, some strains of the virus can cause cervical cancer and death.

For the study, Yale School of Public Health researchers analyzed data from the federal government’s National Immunization Survey on teen girls who received at least one dose of HPV vaccine. During the 2008 to 2009 period studied, 55 percent of the adolescents received all three doses, 24 percent received two doses, and 21 percent received one dose. (Three doses are needed for effective prevention against HPV.) Findings showed African-America, Hispanic and low-income adolescent women were the least likely to complete the full HPV vaccination series.

Why? Well, researchers believe that even though the federal government covers the more than $100-a-shot cost of the three-dose vaccine under the Vaccines for Children program, other factors might prevent young women from attending follow-up appointments. One factor researchers cited was inconvenience—docs recommend young women get the second dose two months after the initial dose and the third dose three to six months after the first dose. This vaccination schedule might make it difficult for working parents with inflexible work schedules to accompany their child to follow-up appointments. Other challenges might include office visit co-payments and transportation costs.

But researchers believe that these problems can be solved. Certainly vaccines cost much less than treatment for stage 3 or 4 cervical cancers, noted one doctor unconnected to the study.

Clinicians diagnose about 12,000 new cervical cancer cases each year, according to the Centers for Disease Control and Prevention (CDC), resulting in about 4,000 deaths. HPV can also lead to vulval, vaginal and anal cancer in women and penile and anal cancers in men.

Click here to read about African-American women’s concerns about the HPV vaccine.