There are various causes for lack of orgasm that include physical, psychological or social causes. The physical causes of the absence of orgasm include medications, hormone abnormalities, depression, and fatigue. The psychological causes could be triggered by negative memories, distraction by stress, certain thoughts, not being able to concentrate and accept the physical sensations. The treatment of the inability to orgasm depends on the causes. You may consult a gynecologist and psychiatrist for further investigations and to determine why, exactly, you are experiencing lack of orgasm.