Pregnancy during the use of levonorgestrel intrauterine system

Comparative contraceptive effectiveness of levonorgestrel-releasing and copper intrauterine devices: the European Active Surveillance Study for Intrauterine Devices

“…A cross-sectional study by Backman in more than 17,000 women, for example, showed a PI of 0.11 [4]. Similar results of 0.1-0.2 were found in reviews of randomized clinical trials [7][8][9].…”

“…The respective ectopic pregnancy rates range from 0.02-0.2 in LNG IUS users and from 0.1-0.8 in copper IUD users [3,4,8,11].…”

“…Contraceptive failure rates for both copper intrauterine devices (IUDs) and levonorgestrel-releasing intrauterine systems (LNG IUSs) are among the lowest for reversible methods of contraception [1,2], with studies of various types showing rates of around 0.1-2.2 per 100 WY for copper IUDs and 0.1-0.6 per 100 WY for LNG IUSs [3][4][5][6][7][8][9][10]. The respective ectopic pregnancy rates range from 0.02-0.2 in LNG IUS users and from 0.1-0.8 in copper IUD users [3,4,8,11].…”

A randomized, phase II study describing the efficacy, bleeding profile, and safety of two low-dose levonorgestrel-releasing intrauterine contraceptive systems and Mirena

“…Efficacy is unaffected by user compliance and reported failure rates are 0-0.6 per 100 women at one year and 0.5-1.1 per hundred women at 5 years (1)(2)(3)(4)(5). Additional benefits of Mirena include a reduction in menstrual blood loss and improvement in dysmenorrhea (6).…”

Comparing the adverse outcomes of contraception failure between IUD and withdrawal methods

“…The rate of ectopic pregnancy with the levonorgestrel IUD was reported to be higher than with the Cu380A in some studies. 11 In our study, 3 cases of ectopic pregnancy occurred, all of whom had used Cu-IUD.…”