Dear Vinod, Thank you for contacting Healthcaremagic. Hi, I have gone through your question and understand your concerns. I understand that you do hand sex (masturbation) two to three times in a week for last five years. Let me address your queries one by one 1. You feel that your penis is not enlarging properly. It seems more due to worries regarding effects of masturbation. Don t worry. Masturbation itself is harmless and will not cause difficulty in erection. So relax and just enjoy pleasurable sensation during masturbation. Do not focus on size and your performance during masturbation. 2. Masturbation doesn t cause HIV. It is myth. 3. Concern regarding penile size is as old as human race. The width and length of penis vary from one individual to another. The normal length of vagina is about six inches. Only outer one third and the front wall of vagina have nerve fibers and hence sensitive to stimulation. Rest of inner two third is largely insensitive. So if you want to arouse your partner during sex, you should focus on the areas of maximum nerve endings hence clitoris and inner lips or labia minora, the outer wall and outer two third of vagina. So for female sexual gratification, the size of erect penis could be anything from two inches or more! You remember that what is important is strength and not the length! Entry and to and fro continuous movements are adequate. It is men s technique, not his penis size that characterizes the lover in him. Bigger is better is Godzilla logic. Hope, I have answered your question. If you have any further questions I will be happy to help. Wish you good health.