The government said Friday it will launch the most far-reaching study of female health ever undertaken, involving hundreds of thousands of women.

Dr. Bernadine Healy, the new director of the National Institutes of Health, said the study would look at the major causes of illness and death in women: cancer, heart disease, stroke and osteoporosis."Women have a right to know how they can prevent and ameliorate the health problems attendant to growing older," Healy told a Senate subcommittee. "The new initiative . . . will go far toward providing these answers."

She said the study would begin with planning and design over the next six to nine months and could cost as much as $500 million over 10 years.

Healy said women experience more disease and debilitating illness than men.

"The good news is that women live longer; the bad news is that their quality of life, from a medical and behavioral perspective, is not what it could be," she said.