英文别名(5R,8R,9S,10R,13S,14S,17R)-13-ethyl-17-ethynyl-17-hydroxy-5-methoxy-2,4,6,7,8,9,10,11,12,14,15,16-dodecahydro-1H-cyclopenta[a]phenanthren-3-one; (5α,17α)-13-Ethyl-17-hydroxy-5-Methoxy-18,19-dinorpregn-20-yn-3-one; 4,5-Dihydro-5α-methoxylevonorgestrel; 4,5-Dihydro-5α-methoxy D-(-)-Norgestrel; Levonorgestrel Impurity O; Levonorgestrel impurity O [EP]; 13-Ethyl-17-hydroxy-5alpha-methoxy-18,19-dinor-17alpha-pregn-20-yn-3-one; 4,5-DIHYDRO-5.ALPHA.-METHOXYLEVONORGESTREL; 18,19-Dinorpregn-20-yn-3-one, 13-ethyl-17-hydroxy-5-methoxy-, (5alpha,17alpha)-; rac-13-Ethyl-17-hydroxy-5alpha-methoxy-18,19-dinor-17alpha-pregn-20-yn-3-one; (1R,3aS,3bR,5aR,9aR,9bS,11aS)-11a-Ethyl-1-ethynyl-1-hydroxy-5a-methoxyhexadecahydro-7H-cyclopenta[a]phenanthren-7-one; (5R,8R,9S,10R,13S,14S,17R)-13-Ethyl-17-ethynyl-17-hydroxy-5-methoxyhexadecahydro-3H-cyclopenta[a]phenanthren-3-one; (5R,8R,9S,10R,13S,14S,17R)-13-ethyl-17-ethynyl-17-hydroxy-5-methoxytetradecahydro-1H-cyclopenta[a]phenanthren-3(2H)-one 
