Norgestrel

Norgestrel (INN, USAN, BAN, JAN) (brand names Logynon, Nordette, Eugynon, Microgynon, Ovran, Ovranette, Trinordiol, numerous others) is a steroidal progestin that has been used in hormonal contraceptives. It is a mixture of two stereoisomers, dextronorgestrel (CAS# 797-64-8) and levonorgestrel (CAS# 797-63-7). Only levonorgestrel is biologically active. Therefore, while some medications may contain dextronorgestrel, they are often labeled in terms of their levonorgestrel content only, ignoring the inert isomer.