Yes, it is possible to get pregnant after tubal ligation, though it’s uncommon. The procedure is highly effective, but it is not 100% reliable. The largest U.S. study on this topic, which followed over 10,600 women for up to 14 years, found that failures continued to occur years after the procedure, not just in the first few months. Your risk depends on the method used, your age when you had the procedure, and how much time has passed.
How Often Tubal Ligation Fails
The most comprehensive data comes from the U.S. Collaborative Review of Sterilization (CREST), a landmark study that tracked thousands of women long-term. Cumulative 10-year pregnancy rates ranged from about 7.5 per 1,000 procedures for the most effective methods to 36.5 per 1,000 for the least effective. That means even with the best technique, roughly 1 in 133 women became pregnant within a decade. With the least reliable method (clip application), approximately 1 in 27 did.
More recent data suggests failure rates may be even higher than previously thought. A study analyzing women sterilized between 2013 and 2015 estimated that 2.9% became pregnant within the first year alone. The risk doesn’t disappear after the first year either. Failures have been documented five or more years after surgery.
Why the Procedure Can Fail
Tubal ligation works by blocking the fallopian tubes so that eggs and sperm can’t meet. When pregnancy occurs afterward, it usually means the tubes have found a way to reconnect or bypass the blockage. There are a few ways this happens.
The most common biological mechanism is the formation of a tiny passage called a fistula, where tissue heals in a way that creates a new channel between the severed or blocked ends of the tube. Essentially, the body repairs itself just enough to let an egg through. Another possibility is recanalization, where the inner lining of the tube slowly regrows and reopens a path. In rare cases, the procedure itself was performed incorrectly. One documented cause of failure is the surgeon mistakenly treating the round ligament (a nearby structure that looks similar) instead of the actual fallopian tube.
Which Methods Are Most and Least Reliable
Not all tubal ligation techniques carry the same failure risk. The CREST study found clear differences across methods at the 10-year mark:
- Clips (spring clip application): Highest failure rate at 36.5 per 1,000 procedures
- Bipolar cautery (burning the tubes closed): Intermediate failure rate
- Unipolar cautery: Among the lowest at 7.5 per 1,000
- Partial salpingectomy after delivery: Also among the lowest at 7.5 per 1,000
Complete removal of both fallopian tubes (bilateral salpingectomy) is the most reliable option. A systematic review of the medical literature found no documented cases of spontaneous pregnancy after both tubes were fully removed for contraceptive purposes. Only four pregnancies have ever been reported after total removal, and all of those occurred in women who had the surgery for other medical reasons such as infection or a prior ectopic pregnancy. This is why many gynecologists now recommend full tube removal instead of traditional ligation when permanent sterilization is the goal, particularly since it also appears to reduce ovarian cancer risk.
Age Matters More Than You’d Expect
Women who are younger when they have the procedure face a significantly higher chance of eventual pregnancy. The CREST data showed this clearly: among women sterilized at a young age using bipolar cautery, the 10-year pregnancy rate was 54.3 per 1,000, roughly 1 in 18. For those who had clips placed at a young age, it was 52.1 per 1,000. Younger tissue may heal and regenerate more aggressively, making fistula formation and recanalization more likely. Women sterilized later in life, when fertility is naturally declining, face lower failure rates both because of the biology of healing and because of reduced baseline fertility.
The Ectopic Pregnancy Risk
This is the most important thing to understand if you’ve had a tubal ligation and suspect you might be pregnant. When pregnancy does occur after the procedure, there is a high chance it will be ectopic, meaning the fertilized egg implants somewhere outside the uterus, usually in the remaining portion of a fallopian tube. Among true sterilization failures, about 33% of resulting pregnancies are ectopic.
An ectopic pregnancy cannot develop normally and is a medical emergency if the tube ruptures. Early symptoms can mimic a normal early pregnancy: a missed period, breast tenderness, nausea, and a positive pregnancy test. The warning signs that distinguish an ectopic pregnancy include light vaginal bleeding paired with pelvic pain, pain in one shoulder, or a feeling of pressure in the rectum. If the tube ruptures, symptoms escalate to severe abdominal pain, extreme lightheadedness, fainting, and signs of shock. This requires emergency treatment.
If you’ve had a tubal ligation and get a positive pregnancy test, contact your doctor immediately. Early diagnosis allows for safer treatment before complications develop.
What a Pregnancy After Tubal Ligation Looks Like
In many cases, women who become pregnant after tubal ligation don’t realize it right away. They may assume their missed period is related to stress or hormonal changes, since they believe pregnancy isn’t possible. A standard home pregnancy test will show a positive result whether the pregnancy is in the uterus or ectopic. An ultrasound is needed to confirm where the pregnancy is located, and blood tests measuring pregnancy hormone levels help determine whether it’s progressing normally or may be ectopic.
If the pregnancy is confirmed to be in the uterus (not ectopic), it can proceed normally. Women who conceive after tubal ligation and carry a uterine pregnancy are not at higher risk for birth defects or complications compared to any other pregnancy. The key step is ruling out an ectopic location as early as possible.