SAN FRANCISCO – A suitable and effective method for relieving pain among women undergoing intrauterine device insertion has eluded investigators, but the search has not been in vain.
Findings from two studies presented at the annual meeting of the American College of Obstetricians and Gynecologists may have failed to demonstrate clearcut improvements in pain management, but they did show improvement in other aspects of the patient experience.
In one randomized controlled study, use of an Allis clamp to stabilize the uterus during device placement failed to improve pain when compared with the use of a single-tooth tenaculum, but Allis clamp use was associated with a reduced risk of bleeding requiring intervention, Dr. Lee Taylor Johnson reported at the meeting.
Dr. Lee Taylor Johnson
Pain scores at the time of placement as measured using a 100-mm visual analog scale were 23.5 mm in 38 patients randomized to undergo placement using an Allis clamp, and 31.5 mm in 40 patients who underwent placement using the tenaculum. The scores at 10 minutes were 4.5 mm and 9 mm, respectively. The scores did not differ significantly between the groups.
However, the tenaculum group required more interventions to stop bleeding with pressure or cauterization (15 patients vs. 1 patient in the Allis clamp group), said Dr. Johnson, who conducted the research with colleagues at the Carilion Clinic Residency Gynecology Clinic in Roanoke, Va. She is now at the Tuba City Healthcare Corporation in Tuba City, Ariz.
Patients included in the study were at least 18 years old and were enrolled between September 2012 and November 2013. The study is the first to compare the effects of different instruments on pain during IUD placement, although multiple studies have looked at other ways to reduce pain, she noted.
“They have looked at NSAIDs, paracervical blocks, lidocaine gel, misoprostol, and nitroglycerin. In 2009 a Cochrane Database Review noted that no interventions that have been properly evaluated reduce pain during or after IUD insertion,” Dr. Johnson said.
Based on the current findings, providers should consider using an Allis clamp during IUD placement to decrease the risk of cervical bleeding following the procedure, she said.
In another study, Dr. Lauren D. Thaxton, of the department of obstetrics and gynecology at the University of New Mexico, Albuquerque, found that the use of nitrous oxide improved satisfaction with pain management.
Dr. Lauren D. Thaxton
The mean pain score among 40 women in the randomized double-blind study who were treated with 50/50 nitrous oxide and oxygen at the time of IUD insertion was 54 mm on a 100 mm visual analog scale, which was not significantly different from the mean of 55 mm in women who received only oxygen. However, satisfaction with pain management, as measured on a 5-point Likert scale, was significantly greater in the nitrous oxide group, she said.
The study included nulliparous women aged 13-45 years.
Nitrous oxide is relatively inexpensive and has few side effects, which are rapidly reversible with 100% oxygen, making it a feasible approach to improving the experience of IUD insertion for many women, according to Dr. Thaxton.
In fact, women in the study reported being willing to pay $20 to $50 out of pocket for nitrous oxide administration at the time of IUD insertion, Dr. Thaxton said.
In a video interview, she speculated that the amnestic and anxiolytic effects of nitrous oxide may play a role in the higher satisfaction scores, and that higher dosing could contribute to better pain relief.
Dr. Rameet H. Singh, also of the University of New Mexico and the principle investigator for the study, said that it only takes about 1 minute to administer 50/50 nitrous oxide and oxygen, and about 90 seconds to achieve 70/30 concentration, so the process doesn’t substantially prolong the insertion process.
Both Dr. Johnson and Dr. Thaxton reported having no financial disclosures. Dr. Singh reported receiving an honorarium for authoring an article on long-acting reversible contraception.