Why is levonorgestrel used in hormonal coil?

A hormonal coil is placed inside the womb and releases levonorgestrel over time. The hormone makes cervical mucus thicker, which restricts sperm movement, and makes the womb lining thinner. These local effects are central to its contraceptive action. Some people also notice lighter bleeding or no bleeding after their body has adjusted.

The coil does not protect against sexually transmitted infections. It may also be used for reasons beyond contraception, depending on the device and your clinician’s advice. Placement and removal should be performed by a trained healthcare professional.

Follow the fitting advice you are given and learn how to check for the threads if your clinician recommends this. Cramping and spotting can occur after insertion. Keep any follow-up appointment, especially if you cannot feel the threads, feel the hard device at the cervix, or develop new pain or unusual discharge.

Read more about [Levonorgestrel](/materials/levonorgestrel/) and the [Hormonal Coil](/treatments/contraception-and-family-planning/hormonal-coil/).

Seek prompt medical advice for worsening pelvic pain, fever, foul-smelling discharge, heavy bleeding, pain during sex, or a positive pregnancy test while the coil is in place. Get urgent help for severe pain, fainting, or heavy bleeding.

Ask how the coil prevents pregnancy, what bleeding changes are expected, how long it is intended to remain in place, how to check its position, and which symptoms require an urgent review.