Progestogen Only Implants


The progestogen-only implant (POIm) is a subdermal rod containing 68mg ENG (etonogestrel), usually sited on the inner upper arm.  Nexplanon is currently the only available POIm in UK and is licensed to last for 3 years.  It works predominantly by blocking ovulation, though it is likely to thicken cervical mucus and thin the endometrial too.  It is one of the most effective contraception methods available, with pregnancy rate at 0.05% (1st year of use; c.f. female sterilisation is 0.5%, male sterilisation is 0.15%).