New Trial Backs Misoprostol for IUD Insertion in Nulligravidas

June 21, 2013

By Anne Harding

NEW YORK (Reuters Health) Jun 21 - When intrauterine devices (IUDs) are placed in women who've never been pregnant, vaginal misoprostol eases insertion but increases cramping, researchers say.

But the co-author of a 2012 review on the topic, who did not participate in the trial, is not convinced by the results.

"Although this recent study is interesting, (I) still believe that the overall evidence suggests that the use of misoprostol for IUD insertion causes more harm than good," Dr. Ashley Waddington of Queens University in Kingston, Ontario, told Reuters Health.

Misoprostol is widely used for cervical ripening, and also before IUD insertion. However, "there are quite consistent findings that not only does misoprostol administration not improve the ease of insertion of IUDs but it also leads to increased unpleasant side effects," Dr. Waddington and her colleague Dr. Robert Reid concluded last year in their review of six controlled trials (see

In the new study, published June 5 in Human Reproduction, Dr. Adriana Scavuzzi of the Instituto de Medicina Integral Prof. Fernando Figueira in Recife, Brazil, and colleagues note that some health care practitioners are reluctant to use IUDs in nulligravidas, due to concerns about difficulty of insertion. They felt that while previous studies of misoprostol for easing use of IUD insertion have not found a reduction in pain, protocol design may have affected the results.

To investigate, Dr. Scavuzzi and her colleagues randomly assigned 179 nulligravidas to receive 400 mcg of misoprostol or placebo vaginally, four hours before IUD insertion. Among the 86 women in the misoprostol group, 28% had cervical dilation of 4 mm or less, versus 58% of the placebo group (p = 0.00005).

Insertion was difficult or very difficult for 27% of the misoprostol group, versus 55% of the placebo group (p=0.0001), the researchers said.

In the misoprostol group, 37% reported moderate to severe pain with insertion and 34% reported a disagreeable or very disagreeable sensation upon insertion, versus 67% and 69%, respectively, in the placebo group.

However, 62% of women in the misoprostol group experienced cramping before insertion, vs 44% of the placebo group.

"The present study showed a positive balance between the benefits and risks of the use of misoprostol; however, it is not feasible to conclude that its use is imperative prior to IUD insertion in nulligravidas and IUD insertion should not be canceled when the medication is unavailable," Dr. Scavuzzi and her team conclude.

Dr. Waddington commended the researchers for seeking ways to promote more widespread use of IUDs and make insertion easier for patients. "It was a reasonably well done study, but I do question why its results are completely in conflict with every other study that's been done on this topic," she said.

In her own experience, Dr. Waddington added, she has found that misoprostol causes so much cramping and discomfort that it actually makes insertion more difficult. "I've really in my own practice abandoned it completely and I've had no problems with that and my patients have had no problems with it," she said.

The rate of difficulty with insertion reported in the current study "made me question the kind of expertise the inserters had," she added. Dr. Waddington estimated that she inserts IUDs in about a dozen patients per week, and experiences difficulty with an insertion about once a month. "I just wonder what criteria they were using to describe what's difficult or very difficult," she added. "Even if this does improve the ease of insertion, subjecting people to side effects really isn't worth it for minimizing something I encounter once a month."

It's possible that the study's emphasis on the difficulty of IUD insertion with nulligravidas may have made both the inserters and the patients more anxious about the procedure, and hence added to the difficulty, Dr. Waddington added. "I found nulliparas typically don't experience that much more pain than multipara patients, they seem to sail through it just fine."

Dr. Scavuzzi did not respond to an interview request by press time.


Hum Repro 2013.


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