Enthusiastic debates over whether men or women receive better medical care have been going on for more than a decade: Why have medical studies so often used only men? Why does breast cancer research get more funding than prostate cancer research? Rarely is there a clean, clear comparison of unfairness and rarer still has anyone done anything about it.

Sen. Olympia Snowe was not the first person to point out the unfairness of insurance companies being more willing to cover Viagra, an impotence cure, than oral contraceptives, but she is in an excellent position to do something about it. In fact, she started well before Viagra became the primary subject of locker rooms and talk shows.

Along with Sen. Harry Reid of Nevada, Sen. Snowe last year introduced legislation that would require any insurance company that covers the costs of prescription drugs to also cover prescription contraceptives. The insurance companies have fought the proposal, but just look silly now that many are paying to have impotence cured around the country. Not all health plans refuse to cover prescription contraceptives, according to the Allan Guttmacher Institute, which found that the pill was covered by 33 percent of fee-for-service plans, 41 percent of preferred provider organizations and 84 percent of health maintenance organizations.

But compare those numbers, 33 years after the pill was introduced, with the discussion around Viagra, which came out just a few weeks ago. Almost all major insurers were willing to cover Viagra, the question was over how many pills a month a man needed. The double standard was obvious and unnecessary.

That is because denying coverage for the pill also is expensive for the companies and ratepayers. It’s no accident that efficiency-minded HMOs are much more likely to cover contraception. A year’s supply of the pill costs $300; the American Journal of Public Health a couple of years ago concluded that was approximately $3,000 less per woman per year than covering pregnancy-related costs. Abortion, by the way, is routinely covered by all types of health insurers.

Sen. Snowe’s argument in sponsoring this legislation is simple and accurate. “Under many of today’s health plans,” she said, “a woman’s insurance often covers a prescription to alleviate allergy symptoms but not a prescription to prevent an unintended and life-altering pregnancy. … At a time when we want to reduce the number of unintended pregnancies, it does not make sense that so many otherwise insured women are denied access to the most effective contraceptives because of a disparity in coverage.”

The benefits of contraception accrue both to women and to the health care system. The Snowe-Reid legislation ably points this out, but it took Viagra to highlight the unfairness of coverage.