Levonelle is an emergency contraceptive (also known as the morning-after pill) that can be up to 98% effective if taken the day after having unprotected sex. It contains a synthetic substance known as levonorgestrel that works in a similar way to the natural hormone progestogen.
The hormone is thought to prevent pregnancy in the following three ways:
Most women can safely take Levonelle as a form of emergency contraception, as long as it is only take once within a single menstrual cycle. It will not be prescribed to women who are already pregnant because it can cause an ectopic pregnancy. Some women may be hypersensitive to the active ingredient (levonorgestrel) and they will also be advised to use a different form of emergency contraception in order to avoid suffering from an allergic reaction.
If you answer yes to any of the following questions you should consult a doctor before taking Levonelle.
The average menstrual cycle lasts 28 days, beginning with a seven day period during which menstruation will usually occur. Following menstruation, the womb lining will thicken so that the egg can be released during ovulation. Finally the body will release progesterone so that the egg can be fertilised.
You can use this form of emergency contraception at any point during the menstrual cycle, as long as you take it within 72 hours of having unprotected sex.
Levonelle is most effective when taken within 12 hours of having unprotected sex. It has been proven to prevent pregnancy with up to 98% effectiveness if taken within this time period.
If more than 72 hours have passed, you can consider an alternative form of emergency contraception, as Levonelle will not be effective. You may be able to take ellaOne, which will prevent pregnancy for up to five days after unprotected sex.