The development of a selective, synthetic progestogen ought to dispel any notion that high intrinsic activity (potency) per se is disadvantageous. Provided there is excellent cycle control with a low incidence of additional actions, the patient can only benefit long-term from the ingestion of biologically active steroids in lower quantities than were formerly available in oral contraceptives. When intrinsic activities for androgenic, oestrogenic or metabolic effects are diminished, it is difficult to conceive the disadvantages for the patient.
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