Skipping Periods: The Pros, the Cons, the Science

Cons

• 63 additional days of hormones.

• Spotting and bleeding between periods, especially during the first few cycles.

• Increase in risks of strokes, heart attacks and blood clots as well as breast, cervical and liver cancers, similar to that associated with other oral contraceptives.

• Potential to mask menstrual complications such as ovarian failure or amenorrhea.

• Menstruation can't be used as a pregnancy indicator. Women who think they may be pregnant while using Seasonale should take a pregnancy test.

• Like other oral contraceptives, Seasonale is not advised for women who smoke, have had a heart attack, blood clots, certain cancer or liver diseases, unexplained vaginal bleeding or those who might be pregnant.

• No data on effects on teenagers. An estimated 1.2 million girls ages 15-19 take oral contraceptives. The Seasonale trial -- as is standard for clinical trials, given consent issues -- included no participants under age 18.

• Limited longitudinal research.

-- Elizabeth Gettelman