Because I still haven't decided how to interpret your post. There's the you agree with me way - that the presence of seven placebo pills does maintain a regular menstrual cycle, and that maintaining it is important for long term reproductive health. In other words, so women who use the pill can still have kids when they decide to go off birth control.
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<br>Or, there is the way you disagree with me interpretation. That the presence of placebo pills would render taking the pill ineffective and that I must be wrong or it wouldn't work.
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<br>I'll give you the benefit of the doubt and go with the former, because otherwise I'd be faced with the prospect that you are completely ignorant and might someday actually find a way to have kids and lower the average IQ by several points.