Estetrol and drospirenone: a novel oral contraceptive

Estetrol (E₄) is a natural human estrogen produced during human pregnancy in the fetal liver with a unique mechanism of action that displays tissue-selective activity, and behaves as a natural selective estrogen receptor modulator. E₄ acts as an estrogen agonist on the vagina, the uterus and the endometrium, and also shows bone-sparing activity. Its mechanism of action results in neutral impact on endocrine, metabolic and hemostatic parameters, compared with other oral contraceptives. In 2021, Health Canada approved the combination 15 mg E₄/3 mg drospirenone (DRSP), the first and only combined oral contraceptive based on the native estrogen E₄, which has been synthesized from plant-based sources. Shortly afterwards, the U.S. Food and Drug Administration (FDA) and the European Medicines Agency (EMA) also approved the combination 14.2 mg E₄/3 mg DRSP as a female contraceptive.