The androgenicity of progestins

Area of Science:

• Endocrinology
• Pharmacology
• Biochemistry

Background:

• Steroid hormones share structural similarities, but minor differences dictate distinct biochemical activities.
• The 19-carbon (androstane) series includes androgens and progestins used in contraceptives, derived from testosterone.
• Removal of carbon 19 from testosterone shifts hormonal effect to progestogenic, yet retains some androgenic activity.

Purpose of the Study:

• To review the androgenic activity of 19-nor progestins used in hormonal contraceptives.
• To discuss the metabolic and symptomatic manifestations of androgenicity.
• To highlight the development and benefits of newer, less androgenic progestins.

Main Methods:

• Review of existing literature on steroid hormone structure-activity relationships.
• Analysis of metabolic pathways and clinical effects of 19-nor progestins.
• Comparison of androgenic profiles between older and newer progestin generations.

Main Results:

• 19-nor progestins exhibit dose-related androgenic effects, impacting glucose tolerance and lipoprotein synthesis.
• Metabolic and symptomatic androgenic effects include acne and weight gain.
• Newer progestins (desogestrel, gestodene, norgestimate) show reduced androgenicity and associated symptoms.

Conclusions:

• Newer progestins offer a reduction in androgenic side effects compared to older compounds.
• Mitigation of androgenic effects may confer long-term cardiovascular benefits, though further epidemiological data is needed.
• Understanding progestin structure-activity is crucial for developing safer and more effective contraceptives.