How does nexplanon prevent pregnancy?

How does nexplanon stop ovulation

Nexplanon releases etonogestrel into the bloodstream. This progestin reaches the pituitary gland and suppresses the surge of luteinizing hormone that normally triggers ovulation. Without that surge, an egg is rarely released.

What happens to cervical mucus and the uterine lining

The same hormone thickens cervical mucus, making it harder for sperm to move through the cervix. It also thins the lining of the uterus, reducing the chance that a fertilized egg could implant.

How long does protection last after insertion

Once placed under the skin of the upper arm, Nexplanon provides continuous release of the hormone for three years. Fertility returns quickly once the implant is removed.

Can the implant move or break and affect effectiveness

If the rod shifts more than a few centimeters or breaks, blood levels of etonogestrel can drop. Women are advised to check the location of the implant periodically and to use backup contraception if they cannot feel it.

Are there medications that reduce its effectiveness

Certain drugs, including some anticonvulsants and the herbal product St. John’s wort, speed up the breakdown of etonogestrel. Doctors usually recommend an additional birth-control method during treatment with these agents.

When does the patent on etonogestrel implants expire

The primary U.S. patent covering Nexplanon expired in 2022, although secondary patents on the inserter device extend market protection into the late 2020s. Biosimilar or generic versions are still in development.