Letizia is not the only one to not really know what it is. The subdermal implant is one of the latest methods to arrive in Italy, and not everyone is familiar with it yet. It is a soft, flexible rod (4 cm long and 2 mm thick) made of a special plastic (ethinyl-vinyl-acetate) that contains a progestin called etonogestrel inside. The implant is inserted under the skin of the inner part of the arm, and releases a small, constant amount of hormone that provides an effective contraceptive action for 36 months. It works like the progestin-only pill, inhibiting ovulation and creating an unwelcoming environment for the sperm and the egg. Using this method, you are protected from an unwanted pregnancy for up to 3 years. It is therefore considered to be a long-acting contraceptive.
The contraceptive effect begins within 24 hours of insertion, and is immediately reversible after implant removal. It can be removed at any time.