Levonorgestrel: Uses, Forms and Safety

Levonorgestrel is a progestogen used in several contraceptive options and in some emergency contraception products.

It is a synthetic hormone related to progesterone. Depending on the product, it may be swallowed as a tablet or released locally from a device placed inside the uterus.

Levonorgestrel can thicken cervical mucus, making it harder for sperm to pass, and can alter the lining of the uterus. In emergency contraception, timing matters because the tablet works mainly by delaying or preventing ovulation; it does not end an established pregnancy.

Levonorgestrel appears in the Combined Pill, some emergency contraception, the Hormonal Coil and the Progestogen-Only Pill. The instructions differ between products, so the name alone does not tell you how often to use it or how soon it is effective.

Other contraceptive choices include non-hormonal methods, a copper intrauterine device, or methods containing a different hormone. Choice can be guided by bleeding pattern, migraine history, breastfeeding, medical conditions, medicines and whether pregnancy prevention is needed occasionally or continuously.

Irregular bleeding, spotting, nausea, breast tenderness, headache or mood changes may occur with levonorgestrel products. These effects vary by form. Levonorgestrel does not protect against sexually transmitted infections, so condoms may still be needed.

Seek prompt medical advice for severe lower abdominal pain, very heavy bleeding, fainting or suspected pregnancy after emergency contraception.

Tell a clinician or pharmacist about epilepsy medicines, tuberculosis treatments, HIV medicines, liver disease and unexplained vaginal bleeding because these may affect the choice or reliability of a product. Follow the instructions for the specific pack or device and arrange review if bleeding changes remain troublesome.