Naproxen or estradiol for bleeding and spotting with the levonorgestrel intrauterine system: a randomized controlled trial

Abstract

The purpose of this study was to evaluate whether oral naproxen or transdermal estradiol decreases bleeding and spotting in women who are initiating the levonorgestrel-releasing intrauterine system. We conducted a randomized controlled trial of naproxen, estradiol, or placebo that was administered over the first 12 weeks of levonorgestrel-releasing intrauterine system use. Participants completed a written bleeding diary. We imputed missing values and performed an intention-to-treat analysis. There were 129 women who were assigned randomly to naproxen (n = 42 women), estradiol (n = 44 women), or placebo (n = 43 women). The naproxen group was more likely to be in the lowest quartile of bleeding and spotting days compared with placebo (42.9% vs 16.3%; P = .03). In the multivariable analysis, the naproxen group had a 10% reduction in bleeding and spotting days (adjusted relative risk, 0.90; 95% confidence interval, 0.84-0.97) compared with placebo. More frequent bleeding and spotting was observed in the estradiol group (adjusted relative risk, 1.25; 95% confidence interval, 1.17-1.34). The administration of naproxen resulted in a reduction in bleeding and spotting days compared with placebo.