5. The pill lowered likelihood of unplanned pregnancies and abortions. When used correctly—taken at the same time every day—the pill's effectiveness rate is about 99 percent, comparable to other hormonal contraceptives. That's far better than older barrier methods like condoms, diaphragms and spermicides, which are about 90 to 95 percent effective when used with every sexual encounter, and the pill may account for a lower rate of unplanned pregnancies and abortions, according to a 2009 Guttmacher Institute study. Note: barrier methods are still vital for preventing sexually transmitted diseases, which the pill doesn't protect against.
6. The pill altered women's sex drives and sex lives. Some research suggests that the pill and other hormonal contraceptives quash a woman's natural sexual urges by lowering levels of the "libido" hormone, testosterone. "But I don't think we have good definitive studies on that," says Berenson. "Sex drive is such a complicated process, usually very dependent on a woman's age, her stress levels, how much sleep she's getting and the culture in which she was raised." Of course, the pill is also credited for ushering in the sexual revolution of the 60s. Without fear of pregnancy, women may have been more "in the mood."
7. The pill inspired the idea for a male pill. Emphasis on "idea," since several pills that have been tested for curtailing a male's fertility haven't made it beyond clinical trials. "There may be a pill for men at some point," says Berenson, "but nobody's talking about it hitting the market any time soon."