The annual incidence of melanoma among white women age 15 to 39 jumped 50 percent from 1980-2004 but remained steady for white men in that age bracket during the same period, the study published in the Journal of Investigative Dermatology said.

Melanoma is a rare type of skin cancer but causes 75 percent of all skin cancer-related deaths, the most of any type of skin cancer.

It is most common among Caucasians living in sunny climates.

The incidence of melanoma among the young women in the study rose to 13.9 cases per 100,000 women from 9.4 cases, said the study, which used data from the National Cancer Institute, part of the U.S. government's National Institutes of Health.

The reason for the increase among young women is unclear, the study said. The researchers recommended additional studies to investigate if changes among young women's recreational sun exposure or increased tanning bed use were responsible.