Nexplanon is a Progestin-Only Contraceptive
Yes, Nexplanon (etonogestrel implant) is definitively a progestin-only contraceptive method that contains no estrogen. 1
Active Ingredient and Mechanism
- Nexplanon contains 68 mg of etonogestrel, a synthetic progestin, as its sole active hormonal ingredient 2, 1
- Etonogestrel is the active metabolite of desogestrel and functions as a progestin-only contraceptive 3, 4
- The implant releases etonogestrel continuously over its approved 3-year duration 2, 1
Classification as Progestin-Only Method
- The CDC's U.S. Medical Eligibility Criteria for Contraceptive Use explicitly classifies Nexplanon under "progestin-only implants" alongside other progestin-only contraceptives like progestin-only pills and depot medroxyprogesterone acetate 5
- The Society for Maternal-Fetal Medicine guidelines list Nexplanon as a long-acting reversible contraceptive (LARC) containing only etonogestrel, with no estrogen component 2
Clinical Implications of Progestin-Only Formulation
- Because Nexplanon contains only progestin, it can be safely used in women who have contraindications to estrogen-containing contraceptives 5
- The progestin-only formulation makes it appropriate for breastfeeding women, as it does not negatively influence lactation when initiated after 1 month postpartum 2, 6
- Women using Nexplanon receive approximately 75-120 ng of etonogestrel daily through breast milk during the first month of use, though this represents an orally active progestin 6
Common Pitfall
A critical distinction: while etonogestrel is a progestin (synthetic progesterone), Nexplanon should be referred to as a "progestin-only" contraceptive, not "progesterone-only," as it contains a synthetic progestin rather than natural progesterone 5, 3