Rates of pregnancy among levonorgestrel and copper intrauterine emergency contraception initiators: Implications for backup contraception recommendations.

Objective: This study assessed the timing, frequency, use of backup method and 1-month pregnancy rates among individuals who had an intrauterine device (IUD) placed as emergency contraception and reported intercourse within 7 days post-placement.

Study Design: In this secondary analysis of a randomized control trial of IUDs for emergency contraception, 518 individuals reporting unprotected intercourse in the preceding 5 days had a 52 mg levonorgestrel intrauterine system (IUS) or 380 mm copper IUD placed outside the first week of their menstrual cycle. All participants were advised to use backup contraception for 7 days. We assessed pregnancy status 1 month after placement by urine testing or, when not available, by survey responses and electronic health record review.  Participants reported whether their first sexual activity after device placement occurred within 7 days of their placement, the frequency of intercourse and whether they used backup contraception.

Results: Rapid return to sexual activity was common and use of backup contraception was rare, regardless of type of IUD placed. Of participants who resumed penile-vaginal intercourse in the first month, most (286/446, 64.1%) participants reported intercourse within 7 days of IUD placement; only 16.4% (74/446) used condoms or withdrawal. No pregnancies occurred among users of the levonorgestrel IUS who reported intercourse within 7 days of placement (0/138, 0.0%, 95% CI 0.0%, 2.6%) nor among users of the 380mm copper IUD (0/148, 0.0%, 95% CI 0.0%, 2.5%).

Conclusion: Pregnancy rates are low after placement of an IUD for emergency contraception, even among the many who resume intercourse within days following IUD placement without use of backup contraception.

Implications: Clinical guidelines should facilitate access to contraception, including elimination of unnecessary recommendations for backup contraception or abstinence in the 7 days following 52 mg levonorgestrel intrauterine system.