Because of their longer life expectancy, women account for six out of 10 glaucoma cases in the U.S. In addition to age being a factor, estrogen may also play a role. Research suggests that declining estrogen levels at an earlier age, such as early menopause, could cause the optic nerve to age faster than normal. This aging might leave the nerve more likely to be damaged by glaucoma. One recent study found that increased levels of estrogen might slow the development of glaucoma.