BAKERSFIELD, Calif. -- Melanoma is currently the seventh-most-common cancer among women, but experts fear that it could be climbing the charts.

Recent studies of less-serious skin cancer cases have revealed a troubling increase among young adult women, so doctors wondered if melanoma, the lethal form of skin cancer, was also on the rise in this age group.

Researchers from the National Cancer Institute analyzed trends in melanoma for men and women aged 15 to 59.

In the 1970s, rates of melanoma increased for young people of both sexes --- 7 percent annually among males and 9 percent each year for females.

However, in 1980, cases leveled off for men but continued to rise in women. Overall, melanoma incidents more than doubled for young women during the study period.

Researchers can't explain the gender split, but they theorize that girls' increased exposure to ultraviolet rays from the sun and from tanning beds could be partly to blame.