The procedure undertaken for female sterilization is usually tubal ligation. The Fallopian tubes may be tied or cut in a surgical procedure, which permanently blocks the tubes. Alternatively, tiny metal implants may be inserted into the Fallopian tubes in a nonsurgical procedure. Over time, scar tissue grows around the implants and permanently blocks the tubes. Either method stops eggs from traveling from the ovaries through the Fallopian tubes, where fertilization usually takes place.