GENEVA, Switzerland - In its first study of women's health around the globe, the World Health Organization said yesterday that the AIDS virus was the leading cause of death and disease among females between the ages of 15 and 44.

Unsafe sex is the leading risk factor in developing countries for these females of childbearing age, with others including lack of access to contraceptives and iron deficiency, WHO said. Throughout the world, one death in five among females in this age group is linked to unsafe sex, according to the U.N. agency.

"Women who do not know how to protect themselves from such infections, or who are unable to do so, face increased risks of death or illness," WHO said in a 91-page report. "So do those who cannot protect themselves from unwanted pregnancy or control their fertility because of lack of access to contraception."

The data were included in a report that attempts to highlight the unequal health treatment a female faces from childbirth through infancy and adolescence into maturity and old age.

WHO's chief, Margaret Chan, noted that women enjoyed a biological advantage because they tend to live six to eight years longer than men. But in many parts of the world they suffer serious disadvantages because of poverty, poorer access to health care, and cultural norms that put a priority on the well-being of men, she said.

Chan called it a "preventable tragedy" that nearly 15 percent of deaths in adult women occur in maternity, according to the statistics from 2004. She said the discrimination extended throughout a female's life, from girlhood diseases that aren't identified because they are not sicknesses affecting boys, to clinical trials and medicines developed on the basis of curing adult males.

"We will not see a significant improvement in the health of women until they are no longer recognized as second-class citizens in many parts of the world," Chan told journalists in Geneva.