LoviOne® contains 1.5mg of the active ingredient levonorgestrel. Levonorgestrel is a progestin, a synthetic version of the naturally occurring hormone progesterone. Levonorgestrel is found in other emergency contraceptive pills, and also some combined oral contraceptives so it’s familiar in the hormonal contraceptive industry.
During the menstrual cycle, a surge of LH is released from the pituitary gland in the brain, causing ovulation to occur. Progesterone levels regulate this surge which occurs halfway through the menstrual cycle. Learn more about the menstrual cycle.
Therefore, levonorgestrel is thought to work by slowing the surge of LH, preventing or delaying ovulation so that the sperm cannot fertilise an egg.
A secondary effect is that levonorgestrel thickens the cervical mucus making the environment a challenge for the travelling sperm to reach the releasing egg.
LoviOne will not prevent pregnancy if ovulation has already occurred as the sperm could have already fertilised the egg. It is also not effective if unprotected sex occurs again after taking the medication.
