WASHINGTON - The government approved on Friday the first birth control pill specially designed to reduce the frequency of women's periods - from once a month to four times a year.
Hence the name: Seasonale.
The pills aren't a new chemical. They contain the same combination of low-dose estrogen and progestin found in many oral contraceptives.
Nor is the idea of menstrual suppression new. For decades, many doctors have told women how they can skip a period by continually taking the active birth control pills in each month's supply and ignoring the week of dummy pills in each packet.
But Seasonale promises to make the option a little more convenient, with packaging that gives women 12 straight weeks of active pills and then a week of dummy pills for their period. And the Food and Drug Administration's approval means menstrual suppression could become more common, as Seasonale's advertising alerts women to the option.
Seasonale isn't perfect, the FDA cautioned.
While women have fewer scheduled periods, studies show Seasonale users have about twice the risk of unexpected "breakthrough" bleeding between periods as woman taking conventional monthly cycle pills, especially in the first few cycles of use.
Maker Barr Laboratories plans to have prescription-only Seasonale in pharmacies by November. Barr wouldn't reveal Seasonale's price but said it will be comparable to other brand-name oral contraceptives, which sell for roughly $1 a pill. Generic versions can cost half that.
The big safety question is whether four periods a year are enough to allow the uterus to shed any tissue that builds up.
A study by Eastern Virginia Medical School, which developed the three-month pill regimen, shows they are. It tracked 682 women taking either Seasonale or regular monthly pills for a year. Seasonale also proved equally effective at preventing pregnancy.