Comparing the TCu380A and a small Nova-T copper IUD: secondary analysis of discontinuation probabilities, bleeding outcomes and satisfaction in nulliparous participants from a 3-year randomized trial

Objectives: To compare discontinuation rates, satisfaction, and bleeding/pain outcomes over 3 years in a nulliparous population randomized to one of two copper IUDs. Study design: We performed secondary analyses of the nulliparous population (n = 927) in a US-based, participant-blinded, randomized trial of the NTCu380-Mini (n = 744) and the TCu380A (n = 183). We calculated overall cumulative Kaplan-Meier IUD discontinuation and reason-specific probabilities by year. At nine timepoints over three years, participants summarized IUD satisfaction (highly satisfied, satisfied, dissatisfied, or highly dissatisfied) and last menstrual bleeding patterns; we analyzed responses over time using generalized linear models and estimating equations (computing odds ratios). On first-year diaries, participants also recorded bleeding and menstrual/intermenstrual pain. Results: Through one and two years, NTCu380-Mini users had lower overall discontinuation probabilities compared to TCu380A users: 24.8% vs. 32.8%, p = 0.03 and 39.6% vs. 48.0%, p = 0.02, respectively. Cumulative three-year rates were 50.1% (NTCu380-Mini) vs. 56.5% (TCu380A), p = 0.06. Through all intervals, NTCu380-Mini users had lower discontinuation rates due to bleeding and/or pain and lower expulsion rates relative to TCu380A users; cumulative three-years rate were 14.5% vs. 26.8%, p < 0.001 and 10.0% vs. 15.1%, p = 0.03, respectively. Participants reported higher satisfaction with the NTCu380-Mini (OR 1.29 [95% CI 1.01–1.64]). In the first year, median number of bleeding/spotting days in a cycle (7.0) did not differ between products, yet some prolonged bleeding outcomes and type of pain showed product differences favoring the NTCu380-Mini. Conclusion: Over 3 years, nulliparous NTCu380-Mini users had lower expulsion and discontinuation rates for bleeding and pain, and they reported higher satisfaction than TCu380A users. Implications: The NTCu380-Mini demonstrates comparative benefits in nulliparous users, with lower rates of early discontinuation due to pain and bleeding and expulsions. As copper IUDs are the only non-hormonal, long-acting reversible contraceptives available, future development should prioritize optimizing device design to minimize side effects while maintaining high contraceptive efficacy.