Brevinor is a combined oral contraceptive pill that is used to prevent pregnancy. It contains two active ingredients, ethinylestradiol and norethisterone, which are synthetic versions of the naturally occurring female sex hormones, estrogen and progesterone. Brevinor works by preventing ovulation, making it difficult for sperm to reach an egg, and altering the lining of the uterus to prevent a fertilized egg from implanting. It is typically taken once daily for 21 days followed by a 7-day break during which a withdrawal bleed, similar to a period, occurs. Brevinor is also prescribed for managing menstrual-related issues such as heavy periods, painful menstruation, or irregular cycles, providing benefits beyond contraception for those who use it.