Healthy Volunteers: Laparoscopy to perform the tubal ligation. A tubal ligation, commonly known as "getting your tubes tied," is a surgical procedure for women to sterilize them. This procedure closes the fallopian tubes, stopping the egg from traveling from the ovary to the uterus and preventing sperm from reaching the fallopian tube to fertilize an egg. In a tubal ligation, fallopian tubes are cut, burned, or blocked with rings, bands or clips. The surgery is effective immediately. Tubal ligations are 99.5% effective as birth control. This procedure is done under general anesthetic. A viewing instrument called a laparoscope is passed through an incision in the belly button to perform a tubal ligation. Two or more incisions are made in the abdomen for other instruments to perform the procedure. During the laparoscopy, we will look for and remove endometrial tissue. A small piece of uterine lining is also obtained for examination and research purposes.