This post consists of a single bit of data but it is a particularly poignant and telling example of the impact of noncompliance. The text is from slide 14 of the set, Maximizing Contraceptive Service Delivery:

Compliance counts in the contraceptive process because a significant portion of contraceptive success is associated with compliance-related issues. Using a rough figure of 10 million U.S. women who might be taking oral contraceptives, every 1% decrease in effectiveness could result in approximately 100,000 unintended pregnancies. That means if one method is just 1% more effective in the long run than another, we may be able to avoid up to 100,000 unintended pregnancies. Moreover, if two methods are equally efficacious, the better the compliance for one method, the better the effectiveness will be for that method.

This slide can be found at
~Compliance Is Critical to the Contraceptive Equation~

The entire slide set, which can be downloaded from the Contraception Online site, begins at
~Maximizing Contraceptive Service Delivery~

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