It is intended to be permanent. It is safe. It doesn't limit sexual pleasure. It makes men sterile by keeping sperm out of the fluid that spurts from the penis during sex. Sperm are the reproductive cells in men.
Pregnancy can happen if a sperm joins with a woman's egg.
Sperm are produced in the testicles. They pass through tubes, the vas deferens, to other glands and mix with seminal fluids to form semen. Vasectomy blocks the vas deferens and keeps sperm out of the seminal fluid. The sperm are absorbed by the body instead of being ejaculated. Vasectomy does not affect masculinity.