Tamoxifen to Reduce Unscheduled Bleeding in New Users of the Levonorgestrel-releasing Intrauterine System (LNG-IUS)

Tamoxifen to Reduce Unscheduled Bleeding in New Users of the Levonorgestrel-releasing Intrauterine System (LNG-IUS)

This study evaluates the ability of tamoxifen to improve frequent or prolonged bleeding in new users of the 52mg levonorgestrel-releasing intrauterine device (IUD). Half of participants will receive a course of tamoxifen three weeks after insertion of the IUD, while the other half of participants will receive a course of placebo.

New users of the LNG IUD will be eligible. Subjects will be randomized to receive tamoxifen 10 mg twice daily for 7 days or placebo. Study drug will be started 3 weeks after placement of the IUD. Subjects will maintain a record of daily bleeding and spotting using an electronic text messaging diary.

Inclusion Criteria:

• initiating use of 52mg levonorgestrel-releasing IUD for contraceptive purposes
• access to reliable cell phone
• willing to receive and respond to daily text or email message to assess bleeding

Exclusion Criteria:

• using IUD for indication other than contraception
• postpartum within 6 months, pregnant, or breastfeeding
• removal and replacement of IUD
• undiagnosed abnormal uterine bleeding prior to placement of IUD
• bleeding dyscrasia
• anti-coagulation use
• active cervicitis
• allergy to tamoxifen
• history of venous thromboembolism
• personal history of breast or uterine malignancy
• use of medication contraindicated with use of tamoxifen (coumadin, letrozole, bromocriptine, rifampicin, aminoglutethimide, phenobarbital)