Oral contraceptive pills (OCPs) are a type of medicine with hormones that are used to prevent pregnancy. They contain either a combination of estrogen and progestin or progestin-only. OCPs work by preventing ovulation, which means that the pills keep the ovaries from releasing an egg. They also cause changes to the mucus in the opening of the uterus, called the cervix, and to the lining of the uterus, called the endometrium. These changes keep sperm from joining the egg.

In addition to preventing pregnancy, OCPs can also be used to address other health conditions, particularly menstrual-related disorders such as menstrual pain, irregular menstruation, fibroids, endometriosis-related pain, and menstrual-related migraines. The FDA has formally approved combined pills for acne for specific brands.

It is important to note that OCPs are a choice made by the patient and her clinician after adequate counseling of risks and benefits. While OCPs are a reliable form of contraception thats easily reversed, they do not prevent the spread of sexually transmitted diseases.