Ectopic Pregnancy after Tubal Ligation

Not Foolproof

Tubal ligation, or having your tubes ties, is a very popular procedure for women who have decided not to have any more children. In the United States, more than 10 million women of childbearing age have had this surgery. But while the surgery works well most of the time, it’s not foolproof, and there are cases of pregnancy following a tubal ligation. If a pregnancy should occur, there’s a high risk that this will take the form of an ectopic or tubal pregnancy.

H. B. Peterson and his colleagues conducted a study to determine the risk for ectopic pregnancy in women after tubal ligation. The researchers found 10,863 women participants who were to undergo tubal sterilization procedures with 178 of them excluded from the study for various reasons. The women were interviewed one year after their surgery, and again after 8-14 years. Most of the women were Caucasian and had born at least two children.

Sterilization Failures

1.3 percent of the women reported pregnancies that were classified as sterilization failures. This accounts for 143 of the women. A full one third of these pregnancies were ectopic in nature. Researchers were able to establish the overall probability of ectopic pregnancy to be at 7.3 for every 1000 procedures, no matter which method of tubal sterilization was employed.

This is not to say that the type of sterilization procedure used did not affect the probability for a tubal pregnancy. Researchers found that a method known as bipolar coagulation had the highest rate of failure with 17.1 ectopic pregnancies for every 1000 surgeries. The lowest risk for ectopic pregnancy was seen with postpartum partial salpingectomy, with a rate of 1.5 ectopic pregnancies for every 1000 procedures.

This may not be persuasive to some women who find some of the less successful methods of tubal sterilization to be more tempting since they are thought to be less risky or easier to reverse by the process known as reanastomosis. On the other hand, age is also a factor in becoming pregnant after sterilization. All of the sterilization methods except for postpartum partial salpingectomy double the probability of ectopic pregnancy in women less than 30 years of age at the time of the sterilization as compared with older women.

The authors of this study found that ectopic pregnancy after a sterilization procedure is not unusual, and is even less so in women younger than 30. This means that a tubal ligation does not rule out ectopic pregnancy and women of childbearing age should be aware that symptoms of pregnancy could signify that a tubal pregnancy has occurred. This is a medical emergency which requires prompt treatment.