According to University of Southern California Scientist Malcolm Pike, a regimen of vigorous exercise to delay puberty and hormone treatments to induce artificial menopause can reduce the risk of breast cancer by as much as 95 percent. The regimen would reduce the amount of estrogen exposed to a woman’s breast tissue by shortening her reproductive life. Pike cited better nutrition, earlier menstruation, and pregnancy occurring later in life as reasons why breast cancer rates have increased in recent decades in industrialized societies. Pike said delayed menarche and early menopause significantly decrease women’s rates of breast cancer, noting that women whose ovaries are removed by age 30 reduce their risk of breast cancer by 85 percent. Pike and other researchers have developed a combination of drugs to create an artificial menopause.