Study Participants' and Clinicians' Experiences With Placement of a Novel Low-Dose Copper Intrauterine Device With a Nitinol Frame in Nulliparous Versus Parous Participants [ID: 1374840]

INTRODUCTION: Clinicians may perceive intrauterine device (IUD) placement to be more challenging for nulliparous versus parous users. This study assesses nulliparous versus parous study participants' and clinicians' experiences with placement of a novel, low-dose copper (175 mm2) IUD with a flexible nitinol frame. METHODS: This single-arm, IRB-approved, phase 3 clinical trial recruited pregnancy-capable people aged 17–45 at 42 U.S. centers. We compared nulliparous and parous participants' experiences for first IUD placement attempt including successful placement, participant-reported pain (on an 11-point numeric pain rating scale), investigator-reported ease of IUD placement (on a 5-point Likert scale), need for mechanical cervical dilation, and uterine perforation. RESULTS: Of 1,620 participants enrolled, 973 (60.1%) reported nulliparity and 647 (39.9%) parity. Successful IUD placement occurred at first attempt for 929 (96.0%) nulliparous versus 625 (96.6%) parous participants. Including second attempts, successful placement occurred for 1,601 (98.8%) participants. Nulliparous participants reported a mean pain score of 5.6 (±2.19) versus 4.0 (±2.55) for parous participants (P<.001), and investigators more frequently reported hard or very hard IUD placement in 81 (8.4%) nulliparous versus 22 (3.4%) parous participants (P<.001). Among nulliparous participants, 203 (21.2%) reported pain-related adverse events associated with placement versus 65 (10.1%) in parous participants (P<.001). Mechanical dilation was required for 202 (20.8%) nulliparous versus 79 (12.2%) parous participants (P<.001). Uterine perforation occurred in 1 nulliparous (0.10%) and 1 parous participant (0.15%). CONCLUSION: Despite experiencing more challenging IUD placements than parous participants, nulliparous trial participants experienced similar IUD placement success with this novel, low-dose copper IUD.