Menstrual cup use is becoming increasingly popular as an option for menstrual hygiene among women in the United States, but little is known about the potential for IUD expulsion with menstrual cup use, Jill Long, MD, said at the 2020 virtual meeting of the American College of Obstetricians and Gynecologists.
Dr. Jill E. Long
Dr. Long cited a 2019 Internet survey of IUD users in which 11% reported menstrual cup use; reports of IUD expulsion were approximately three times higher among menstrual cup users. The results of the survey were limited by the self-reported responses and lack of data on when the expulsions occurred related to menstrual cup use.
Similar concerns about expulsion surfaced in an ongoing phase 3, randomized trial designed to support the marketing application of the Mona Lisa NT Cu380 Mini IUD, which is not currently approved in the United States.
“Nine months into the study, more expulsions were observed than expected, particularly among menstrual cup users,” said Dr. Long, medical officer and project officer for the Contraceptive Clinical Trials Network at the Eunice Kennedy Shriver National Institute of Child Health and Human Development. The researchers then began to advise study participants to avoid menstrual cup use, and to collect data on use of menstrual hygiene products.
The preliminary study results reported by Dr. Long included 1,092 women assigned in a 4:1 ratio to receive the Mona Lisa NT Cu380 Mini and ParaGard, an IUD approved in the United States. Participants had follow-up visits at 6 weeks and at 3, 6, 12, 24, and 36 months after placement to verify the IUD position.
At 34 months, the overall rate of IUD expulsion was 9%. Of 277 women who reported menstrual cup use, the expulsion rate was 18%, compared with a 6% expulsion rates among the 704 women who reported tampon use.
Patient behavior persists despite advisory
Overall IUD expulsion was not significantly different among patients enrolled before and after the advisory against menstrual cup use (9.8% vs. 8.8%, respectively). In addition, menstrual cup use did not decrease after the implementation of the advisory (24% preadvisory vs. 28% post advisory).
The expulsion rates between menstrual cup users and nonusers were significantly different at both 12 months (14% vs. 5%) and 24 months (21% vs. 6%).
In addition, the researchers created a category of accidental self-removal, defined as the percent of expulsions occurring at the time the menstrual hygiene product was removed. Accidental self-removal was significantly higher among menstrual cup users, compared with tampon users (43% vs. 10%).
Study limitations included study blinding with regard to IUD type, parity, and age, so the impact of these factors on expulsion remains unclear, Dr. Long said. In addition, data on menstrual hygiene product use was collected retrospectively for the first 9 months, and no data were available on the impact on expulsion of combined use of menstrual cups and tampons.
Despite the apparent lack of impact of counseling, “women should be informed of the increased risk of expulsion if they choose to use menstrual cups concurrently with copper IUDs,” Dr. Long concluded.