Desogestrel ≥ 99%

Desogestrel is a 19-nortestosterone prodrug whose active metabolite, 3-keto-desogestrel (etonogestrel), is a highly selective progesterone receptor (PR) agonist with sub-nanomolar affinity (Ki). Its primary functional outcome is potent anti-gonadotropic activity, achieved by mediating transcriptional regulation that inhibits the mid-cycle luteinizing hormone (LH) surge and pituitary gonadotropin release, thus preventing ovulation. Concurrently, it alters the endometrium and thickens cervical mucus to prevent implantation. The defining strategic advantage of etonogestrel is its high progesterone receptor affinity coupled with low androgen receptor affinity, enabling effective ovulation inhibition at a 0.06 mg/day dose with reduced androgenic side effects compared to earlier progestins.