When they say that semen loss is bad, it's not entirely untrue. My doctor told me the same thing. My wife and I are trying to get pregnant and my doctor recommended me to avoid masturbation and to have intercourse every three days. Leaving a few days in between intercourse helps sperm increase in number and strength. Men who masturbate often will notice that their semen amount reduces. Most of us have experienced it at adolescence when we discovered masturbation.