Substantial changes in women’s health and life expectancy have occurred over the past 100 years. At the beginning of the twentieth century, in much of the Western industrialized world, life expectancy at birth for women was less than 50 years. Life expectancy at birth for women in most industrialized countries is now well into the late 70s and the early mid-80s, on average about seven to eight years longer than men. By age 65 and over, this gender gap narrows, and by age 85, life expectancy for women is very close to men’s. Life expectancy is increasing in all countries. The worldwide birth rate is slowing down, which means that the proportion of older women will increase substantially as well as numbers.