Desogestrel is a synthetic progestin and the active ingredient in Cerelle. It is generally used to suppress ovulation and is effective in preventing pregnancy when taken as directed.
How does Cerelle work
Cerelle works to prevent pregnancy by preventing ovulation (the release of an egg from the ovary). In addition, it is believed to thicken cervical mucous and make it more difficult for sperm to move through the uterus and enter the fallopian tubes. It may also change the lining of the uterus, which makes it difficult for a fertilized egg to implant.
How long does Cerelle take to work
Cerelle can take varied amounts of time to start working, depending on when you take it in your menstrual cycle. If you start consuming Cerelle on days one to five of your period, you will be protected from pregnancy immediately. If you start taking it after day five then it will not work for 48 hours, so you will need to use protection for the first 2 days of taking it to prevent pregnancy from taking place.