Levonorgestrel EP impurity A13-ethyl-17-hydroxy-18,19-dinor-17a-pregna-4,8(14)-dien-20-yn-3-one18,19-Dinorpregna-4,8(14)-dien-20-yn-3-one, 13-ethyl-17-hydroxy-, (17α)-(9R,10R,13S,17R)-13-ethyl-17-ethynyl-17-hydroxy-1,2,6,7,9,10,11,12,15,16-decahydrocyclopenta[a]phenanthren-3-oneLevonorgestrel EP Impurity AQ: What is Levonorgestrel EP Impurity A Q: What is the CAS Number of Levonorgestrel EP Impurity A