I'm not sure the general guideline to start soon after the start of a period is related to efficacy, because HBC is equally effective after seven days whether you take it on the third day of bleeding or in the middle of your cycle.
My understanding is that the guideline is essentially trying to reduce the chance of breakthrough bleeding -- as I've read it, it's more common if you start HBC later in your cycle, and as that is the number one cause for people to discontinue a brand, pill companies want to minimize the chance it will occur.
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Date: 2011-06-07 08:15 pm (UTC)My understanding is that the guideline is essentially trying to reduce the chance of breakthrough bleeding -- as I've read it, it's more common if you start HBC later in your cycle, and as that is the number one cause for people to discontinue a brand, pill companies want to minimize the chance it will occur.