Vasectomy is a male sterilisation surgery performed on men to prevent them having any more children. It is the safest & most effective method of birth control. A vasectomy stops sperms from being added to your semen or ejaculate.
Your semen is made up of various fluids, and other components, including sperms. Semen is mainly produced by the prostate and seminal vesicles.
Sperms are formed in the testes and are carried to the semen via two tubes called the vas deferens. A vasectomy cuts and seals the vas deferens, so that the sperms cannot mix with the semen. As a result, you will ejaculate semen without sperm.
Sperm is the part of the semen that leads to pregnancy. A man cannot make his partner pregnant without sperm.