There’s no 100 percent effective form of birth control. Even tubal ligation procedures can fail and an unwanted pregnancy can occur. In fact, it's estimated as many as 10 out of every 1,000 women who undergo this procedure will have an unwanted pregnancy. If a tubal ligation failure occurs and pregnancy does result, there's an increased risk for an ectopic pregnancy. There are different methods used to conduct the tubal ligation procedure, and each method has a different success rate. There are certain preventative steps that can be taken as well to prevent an unwanted pregnancy after a tubal ligation procedure.
Tubal Ligation Procedure
The tubal ligation procedure involves blocking or severing the fallopian tubes to prevent pregnancy. This is done by cutting, cauterizing, clipping or stitching the fallopian tubes. Sometimes, multiple methods are used. Although this is considered to be the most effective form of permanent birth control, there’s a slight failure rate, which has shown to increase 10 years after the procedure was conducted. Younger women appear to have a higher failure rate with the procedure because they are more fertile than older women.
Causes of Failure
One cause of a tubal ligation failure is due to contraception prior to the procedure. An early pregnancy can often be undetected until after the procedure has been conducted. If this occurs, however, it isn’t considered to be a failure of the procedure itself.
A common cause of a tubal ligation to fail is when the fallopian tubes spontaneously reconnect. This often occurs if the gap between the tubes wasn’t large enough or if a fallopian tube ring or clip slips out of place. For this reason, when clips are used during the procedure, it’s considered to be one of the less effective forms of tubal ligation.
If the tubal ligation procedure is conducted poorly or improperly, there’s a higher risk of failure as well. If the tubes haven’t been completely severed or clipped, the failure rate increases. In some cases, the round ligaments can be mistaken for the fallopian tubes, and as a result the wrong tubes are cut, leaving the fallopian tubes connected.
Although the failure of a tubal ligation procedure can’t be completely prevented, there are certain precautions that can be taken to reduce the risk for failure. For example, it’s essential women undergo a same day pregnancy test to ensure they haven’t already conceived prior to the procedure. The use of contraception prior to the tubal ligation procedure is equally as important.
If the procedure is conducted during menstruation or postpartum there’s a higher success rate with the sterilization. It’s often recommended if an IUD device was used prior to the procedure it remains intact until after the following menstruation period. If the hysteroscopic procedure was used to perform the tubal ligation, a second form of contraceptive should continue to be used until it’s confirmed the fallopian tubes have been completely blocked with scar tissue.
"Tubal Ligation Failure" https://www.healthhype.com/tubal-ligation-failure-causes-of-pregnancy-after-sterilization.html
"Tubal Ligation" https://www.sogc.org/health/health-tubal_e.asp