Comparison of Estrogenic Components Used for Hormonal Contraception

Attempts have been made over the years to replace ethinyl estradiol (EE) in combined oral contraceptives (COCs) with the less potent natural estrogen estradiol (E2), or its prodrug, E2 valerate (E2V), to improve the safety and tolerability of COCs. Recently, a COC formulation incorporating a novel weak natural estrogen, estetrol (E4), combined with drospirenone, has become available. Here we present a comparative analysis of the three prevailing estrogens used in COCs, focusing on their structure-function relationships, receptor-binding affinity, potency, metabolism, pharmacokinetic parameters, and pharmacodynamics.

Source: Contraception - October 18, 2023 Category: OBGYN Authors: Frank Z. Stanczyk, Sharon A. Winer, Jean-Michel Foidart, David F. Archer Source Type: research