Up to 1 in 20 People Can Get Pregnant After Tubal Sterilization Procedure

By Melinda Young

Permanent contraception may not be as permanent as people think. New research shows the challenges physicians have when providing contraceptive counseling to patients who do not want to be pregnant now or in the future. Their method of choice — tubal sterilization — does not prevent future pregnancies in at least 2.9% to 5.2% of the people who have this procedure.¹

“It seems high, and it begs the question of whether we should use the word ‘permanent’ or call it a surgical contraceptive procedure,” says Eleanor Bimla Schwarz, MD, MS, professor of medicine and chief of the division of general internal medicine in the School of Medicine at the University of California San Francisco.

“We should recognize that all contraception has failure rates,” she says. “And these surgeries are not reversible; if they change their minds, it will be very difficult, expensive, and possibly not possible to become pregnant — especially for people with publicly funded healthcare, which does not usually cover [some] fertility services.”

Although most of the tubal procedure failures are related to tubal ligation, even removing the person’s tubes does not provide pregnancy protection 100% of the time, she notes.

“There have been people reporting pregnancy after their tubes were taken out,” Schwarz says. “When people have limited access to abortion, it becomes scary.”

The new study uses data from the National Survey of Family Growth (NSFG), spanning more than a decade. Investigators identified people who had a tubal sterilization based on their answering “yes” to the question of whether they had ever had both of their tubes tied, cut, or removed.¹

Researchers identified pregnancies among those who had the surgical procedure and noted the month and year of conception. They hypothesized that pregnancy is less common after procedures among older women and among women who had a postpartum tubal sterilization procedure.¹

The study’s findings are similar to data Schwarz and co-investigators previously published based on an analysis of California Medicaid data, Schwarz says.

“We looked at rates of pregnancy with laparoscopic tubal ligation among Medicaid clients, and 2.64% were pregnant within one year,” she says. “In this more recent study that looked at not just California but the National Survey of Family Growth across the United States, rates ranged from 2.9% to 5.2%, within one year after the surgical procedure.”¹

Among the survey data from 2013 to 2015, the estimated percentage of participants with pregnancies within the first 12 months after a tubal sterilization procedure was 2.9%. Within 120 months, the estimated percentage was 8.4%, the study found.¹

Earlier research, such as the CREST study, found a smaller risk of failure after tubal contraceptive surgery. That work led to outdated effectiveness data when professional societies and clinicians counsel patients considering permanent contraception. The new study should be used when counseling patients because it shows an estimated failure rate of four to five times higher than estimates given in the older CREST study, according to a paper about the new study.²

As the new paper notes, the higher-than-expected procedural failure of tubal contraceptive surgery can lead to unintended pregnancies for women who then are forced to carry the pregnancy to term because they lack resources to obtain an abortion. Obligatory parenthood is the outcome for people with the fewest resources and most structural disadvantage, the authors said.²

What the new research findings suggest is that OB/GYNs and other reproductive health providers need to include this information in their contraceptive counseling with patients.

“We base all of what we do on the idea that our patients know what’s best for them based on their complicated life situation, and our job is to talk about all their options,” Schwarz says. “We have to base that on available data, and if their number one issue is how it works at preventing pregnancy, then our answer has to be the most effective method is the contraceptive arm implant; number two is vasectomy; number three is the hormonal IUD; number four is a surgical procedure, and number five is the copper IUD.”

“There are small differences in pregnancy rates between those methods, but the honest answer to a patient is that there are reversible methods that are likely to be more effective,” Schwarz explains.

Hysterectomy is not recommended as a contraceptive procedure because of the significant risk of surgical complications, she adds.

More research is needed to clarify the relative effectiveness of the various procedures used in permanent contraception, including partial salpingectomy, complete salpingectomy, band, clip, and monopolar or bipolar fulguration, and others, according to the paper about the new study.²

If a physician has a patient who — for health or other reasons — says she cannot get pregnant and to whom an abortion would not be available in her state, then the contraceptive discussion could go like this: “I would say, ‘What do you think about an arm implant?’ and if they tried it and didn’t like it, then I’d ask, ‘What do you think about the hormonal IUD?’” Schwarz says. “If they had tried the IUD and didn’t like it, I would suggest they talk to their partner about vasectomy and also would discuss the surgical procedure.”

From a woman’s perspective, vasectomy is the safest and most effective, she adds.

Previous research has used data from publicly funded patients, and one argument against acknowledging data on the higher-than-expected pregnancy rates has been that people with public insurance have less positive healthcare experiences, and that is why they have more failures, she notes.

But the new study discredits that hypothesis. “We looked at people with both public and private insurance and didn’t see any difference in failure rates by the funding of insurance, race, or ethnicity,” Schwarz says.

“The big thing that impacts the rates is her age and whether the procedure was done right after birth or not,” she explains. “If she’s older, she’s more likely to not become pregnant.”

Another factor to consider in counseling patients about sterilization procedures is regret.

“Ten percent of U.S. women who have a surgical contraceptive procedure go on to regret having that surgery, and that 10% is painfully high,” Schwarz says. “Those regrets reflect the misunderstanding that if you have your tubes tied, you can untie them, which is not the case, and it may not work as well as some people think it does.”

The overturn of Roe v. Wade makes these discussions even more important.

“I think it raises the question of are we doing a good enough job of counseling people about all of their options,” she says. “There is widespread misunderstanding that surgical contraception is the most effective option. And if people do not have the back-up of abortion, effectiveness really matters a lot to them.”

It is time to update sterilization policy and make sure all women who are considering surgical contraception are well informed, she adds.

It also may be time to eliminate contraceptive barriers that prevent some women from obtaining what could be their preferred method, such as the highly effective contraceptive implant.

“Even though placing an implant is a simple procedure, it requires formal FDA training, and not everyone is able to place an implant,” Schwarz says.

The mandated training program requires several hours of in-person training, which does not make the implant more effective at preventing pregnancy, but results in fewer clinicians who are able to provide the implant to patients, she explains.

“I think everybody should be able to choose the method that’s right for them after being well-informed about what all their options are,” Schwarz says.

References

1. Schwarz EB, Chiang AY, Lewis CA, et al. Pregnancy after tubal sterilization in the United States, 2002 to 2015. NEJM Evid 2024;3:1-10.
2. Tasset J, Rodriguez M. “Permanent” contraception — reexamining modern tubal sterilization effectiveness. NEJM Evid 2024;10.1056/EVIDe2400263. [Online ahead of print].