Yes - I thought it was because I missed one day and didnt notice for a couple days. i didnt take the brown pills last month and never had a period. Im due for mine to start soon. I am taking the brown pills this month and praying that I dont miss another period. I have been on this since March of 2007 and have gained 20lbs which I can not afford to gain. I m going to the Gyno at the end of this month and am planning to speak with her about the alternatives.