Abstract
Since its introduction in 1960, the combined oral contraceptive (COC) pill has become
one of the most widely and frequently used methods of contraception worldwide. Although
highly effective, early COC formulations were associated with significant adverse
effects and unacceptable cardiovascular risk. Improvements in tolerability and safety
have been achieved, without compromises in effectiveness, primarily via hormone dosage
reductions and the development of several new progestins. Multiphasic COCs and extended-/continuous-cycle
COCs have also been introduced, although the clinical advantages of these formulations
vs. traditional COCs have yet to be established. Inclusion of natural estrogens such
as estradiol valerate and 17β-estradiol with selective progestins in new combinations
that maintain good cycle control is the most recent evolutionary step designed to
improve COC tolerability and safety. Vigorous research needs to continue to help guarantee
that the unmet need for safe and effective contraception is satisfied in future generations.
Keywords
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Article info
Publication history
Published online: December 27, 2010
Accepted:
November 3,
2010
Received in revised form:
November 3,
2010
Received:
March 5,
2010
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© 2011 Elsevier Inc. Published by Elsevier Inc. All rights reserved.
