Avoid hormone replacement therapy as this will seriously mess you up (there are studies that link them to breast cancer).  On the subject of hormone replacement therapy, birth control pills are in essence low dose hormone replacement therapy so you should avoid those too.

Things that help...  Stop smoking, maintain your weight (fat is a secondary source of estrogen, exercise, take vitamin D, vitamin E, calcium, soybeans (it's a natural estrogen), phytoestrogens, vitamin E, black cohosh, chaste tree berry, dong quai, ginseng, hops, licorice (glycyrrhizin free variant), wild yams (this is debatable), and red clover.