Tamoxifen Versus Estradiol for Unscheduled Bleeding in Etonogestrel Implant Users, a Randomized Pilot Trial

Tamoxifen Versus Estradiol in the Prevention of Unscheduled Bleeding in Etonogestrel Implant Users, a Randomized Controlled Pilot Trial

The purpose of this research study is to evaluate the ability of medicines called tamoxifen or estradiol to prevent annoying vaginal bleeding for arm implant users.

This pilot study compares the use of tamoxifen to estradiol to placebo for seven days once a month up to 5 months in contraceptive implant users starting from the time of implant initiation. Participants will record bleeding and satisfaction response in a daily text diary.

Inclusion Criteria:

• etonogestrel implant users
• at time of and/or within 21 days of initial use of etonogestrel implant placement
• must agree not to take additional hormonal therapy during the study trial period

Exclusion Criteria:

• within 6 months following vaginal or cesarean delivery
• within 6 weeks following abortion
• currently breastfeeding
• positive pregnancy test
• contraindications to tamoxifen or estrogen
• history of thromboembolism
• undiagnosed abnormal uterine bleeding
• active cervicitis
• bleeding disorder
• use of anticoagulation medications
• an unwillingness or inability to keep a daily menstrual diary or to follow the study criteria