Norethindrone Structure (Norethindrone)
Norethindrone is a type of hormone used in some forms of birth control. It is a progestin, and works by thickening cervical mucus to prevent sperm from reaching the egg, as well as thinning the lining of the uterus to make implantation less likely. It is also sometimes used to treat endometriosis, irregular periods, and other hormonal imbalances.*