NEW YORK (Reuters Health) – The titanium clip should not be used for postpartum sterilization until further study can show its efficacy, according to the authors of a new systematic review.

Postpartum sterilization is done within six weeks of delivery, although it is usually performed within 48 hours after birth, Dr. Maria I. Rodriguez of the World Health Organization in Geneva and her colleagues explain in the July issue of Obstetrics & Gynecology. The titanium clip is increasingly being used for postpartum sterilization, they add, although data on its effectiveness in this setting is lacking.

To investigate, the researchers looked at 10 observational trials and three reports from a single randomized, controlled trial, all investigating postpartum sterilization with the titanium clip and using subsequent pregnancy as an outcome.

The randomized controlled trial, which compared the clip to partial salpingectomy, found a significantly increased risk of pregnancy at 24 months among women who received the titanium clip. The cumulative pregnancy rate for women treated with the clip was 1.7, compared to 0.04 for women who had salpingectomy.

The remaining studies were observational, with results ranging from no difference in effectiveness from the comparison method to an 8.4 percent pregnancy rate over two years following the procedure.

“Although data to support the use of the titanium clip for postpartum sterilization are limited, the existing data are concerning, especially for long-term outcomes,” the researchers say.

Increased edema in the fallopian tubes postpartum could account for the decreased efficacy of the titanium clip, they add.

While the titanium clip may be appropriate for postpartum use in “technically difficult” cases, for example for women with prior cesarean sections or who are morbidly obese, alternatives to postpartum sterilization should also be suggested when counseling these women, the researchers say.

They conclude: “A well-designed clinical trial documenting the long-term efficacy of the titanium clip in the postpartum patient is needed before the technique is offered and used routinely in this population.”

Obstet Gynecol 2011;118:143-147.