"Getting your tubes tied" is a colloquial way to say that someone is undergoing tubal ligation, a sterilizing surgical procedure that involves closing off the fallopian tubes.
In non-medically assisted pregnancy, an egg travels from the ovary to the uterus via the fallopian tubes, also called uterine tubes. Tubal ligation prevents this movement by permanently blocking, clipping or removing the tubes, thus keeping the egg from becoming fertilized. The removal of the tubes, called a salpingectomy, is a type of tubal ligation.
