Kyleena will last for up to five years and is over 99% effective at preventing pregnancy for this time.

However, you do not have to wait for five years if you decide you want to become pregnant. The effects of Kyleena are instantly reversible. As soon as Kyleena is removed by a trained health care professional your fertility levels will rapidly return to what is normal for you. This means that you can become pregnant as soon as Kyleena is removed and studies have shown that 7 out of every 10 women who want to become pregnant will have conceived within one year of Kyleena being removed.

How does Kyleena work?

Kyleena releases a continuous, low-dose of levonorgestrel (a progesterone hormone) which is thought to prevent pregnancy by thickening cervical mucus which prevents the passage of sperm into the uterus, inhibiting the motility of sperm and their survival, and changing the endometrium so it is unable to accommodate a fertilized egg.

Kyleena contains a total dose of 19.5 mg of levonorgestrel (LNG) which is designed to be released slowly over five years. The rate of release varies depending on the time since insertion. Initially, a bigger dose of LNG is released, reaching a peak after 24 days of 17.5 mcg/day. This rate decreases progressively from 9.8 mcg/day after 1 year to 7.4 mcg/day after 5 years.