<s>[INST] hi doctor, i am 25 years old and i faced a problem today that my penis does get hard when i masturbate ( I have been masturbating since 15 years old once each 2 days) . Also, i don't have sex often, it's just once every month. last 2 months i had a girl friend and i found out that some times while we having sex my penis dies!!should i stopp masturbating? and does the past 10 years of masturbating going to affect my sexual life? and why do my penis dies while i'm having sex? [/INST] Hello, Following is my opinion about your case. The masturbation has no effect on erection. During sexual arousal you can practice intercourse. You might not get penis erection due to stress which is a common cause of erectile dysfunction in a young age grouped person. You can practice more foreplay while doing sexual intercourse.  You can restrict masturbation frequency 2-3 times a week. Hope I have answered your query. Let me know if I can assist you further. Take care Regards, Dr. Parth Goswami, General & Family Physician </s>