Semen is not a baby
Semen is considered a living organism. By masturbating you are killing potential children that could of had life that was unique to that spermatozoa.
For a long time masturbating was taboo and not allowed because you are killing children, which they are technically correct.
So while we are outlawing abortion we may as well outlaw procrastination.
Semen are cells, fetuses are cells. What's the difference?