Pathophysiology

Tubal ligation

During the procedure the tubes are ligated, clipped, electrocoagulated, banded, or plugged.  This interrupts the patency of the fallopian tubes, thus preventing the ovum and the sperm from meeting.  
Complications of female sterilization procedures include coagulation burns in the bowel, bowel perforation, pain, infection, hemorrhage, and adverse anesthesia effects.  
Reversal of a tubal ligation depends on the type of procedure performed.  A pregnancy can be achieved up to 75% of the time after mechanical occlusion as compared with electrocoagulation, because more tissue is destroyed in the latter procedure.

Davidson, M.R., London, M.L. & Ladewig, W.P. (2008). Old’s Maternal-newborn nursing and women’s health across the lifespan (8th ed.) Upper Saddle River, NJ: Prentice-Hall.