TOPIC

Levonorgestrel

by The Lowdown · May 24, 2021

by Dr Melanie Davis-Hall · May 24, 2021

One of the most commonly-used progestogens in contraception, levonorgestrel is found in combined pills, progestogen-only/mini pills (POP), the hormonal coil (IUS) and the morning after pill.

Levonorgestrel is the well-travelled aunt of the progestin world. As one of the most commonly-used progestogens in contraception, levonorgestrel is found in combined pills, progestogen-only/mini pills (POP), the hormonal coil (IUS) and the morning after pill.

The reason levonorgestrel gets around so much is that it’s a relatively old synthetic progestin, developed when there were fewer options on the market. It belongs to the second-generation class of progestins, which were derived from testosterone.

How does it work?

When taken as the morning after pill, levonorgestrel is thought to work by preventing ovulation if it hasn’t already occurred. When taken as a longer-term contraceptive orally or in an intrauterine device (hormonal coil), it can also prevent ovulation and stop sperm from getting to your uterus by thickening your cervical fluid. It can also make the lining of your womb thicker, making it trickier for a fertilised egg to implant.

What it is used in?

Levonorgestrel is found in the following brands:

Combined pills

Progestogen-only pills

Hormonal coil (IUS)

Morning after pill 

  • Levonelle

Is it androgenic?

Yes1. (Check out our ‘Androgens’ blog for more info on what this means).

What are the side effects?

Depending on how and when women take levonorgestrel, for example in the form of a combined pill where it is used in combination with oestrogen, or in the hormonal coil where it inserted into the womb, side effects can vary.

The following side effects have been noted:2 3 4

With the hormonal coil (IUS or intrauterine system)

  • Changes to your periods including irregular bleeding or your periods stopping altogether
  • Acne
  • Headaches
  • Breast tenderness
  • Changes in mood
  • Back pain
  • Ovarian cysts
  • Pelvic disorders
  • Vulvovaginal disorders and infections
  • Weight changes

With the combined pill

  • Breast tenderness and enlargement
  • Headaches
  • Nausea
  • Mood changes
  • Increase in blood pressure

Tags
  1. Stankzyk FZ. All progestins are not created equal. Steroids. 2003. Volume 68, Issues 10–13. P879-890. Available from: https://doi.org/10.1016/j.steroids.2003.08.003
  2. Joint Formulary Committee. British National Formulary (online) London: BMJ Group and Pharmaceutical Press <https://bnf.nice.org.uk/drug/levonorgestrel.html> [Accessed on [13 August 2020]]
  3. Family Planning Association. IUS (Intrauterine system). Jan 2021. Available at https://www.sexwise.org.uk/contraception/ius-intrauterine-system
  4. Family Planning Association. Combined pill (COC). Mar 2021. Available at https://www.sexwise.org.uk/contraception/combined-pill-coc