"i took this medication for 2 years and found little trouble with it. occasionally i would have longer periods, but more often than not i wouldn&#039;t have one at all. on average, i&#039;d say i had a period every 2 months and every 4th period lasted for a week. i took this as an alternative to most birth controls, which were giving me migraines. this one only gave me a slight headache around the last couple days of the inactive pills and the first couple of days starting a new month, but nothing too terrible."