Essure is not immediately effective and works by causing scar tissue to grow over the micro inserts over time, blocking the fallopian tubes.
Three months after the device is placed, a hysterosalpingogram (dye test of the fallopian tubes) is done to prove that the tubes are blocked before allowing the patient to have unprotected sex. (An alternate birth control method must be used for three months).
The procedure takes about 35 minutes, can be done in the office or ambulatory surgery center, is non hormonal and well tolerated, and has few risks and complications.
Insertion should be done in the first half of the cycle, before ovulation, to decrease the chance that undiagnosed pregnancy has occurred and to increase the visualization of the tubal openings (in the latter half of the cycle the lining may be too thick, making visualization of the tubal openings harder), and it should not be done during menses. In some patients (14% in one study) micro inserts were unable to be placed.
Patients go home from the office or from the ambulatory care center and can go back to work in 24 hours.