Using etonogestrel implant for emergency contraception
Official title: Etonogestrel Implant as Emergency Contraception: A Pilot Pharmacodynamic Study
Run by University of Colorado, Denver · NCT05237141 · Data updated 2026-11-12
This study is testing if an etonogestrel implant can work as emergency contraception by preventing ovulation when it's inserted before a certain hormone surge in women with regular menstrual cycles.
Quick facts
| Phase | Phase 4 |
|---|---|
| Study type | Interventional |
| Ages | 18 Years to 40 Years |
| Sex | Women only |
| Enrollment | 12 (estimated) |
| Sponsor | University of Colorado, Denver Academic / other |
| Locations | 1 site (Aurora, Colorado) |
| Status | Recruiting |
| Started | April 1, 2022 |
| Main results expected | December 2027 |
| Study ends | December 2027 |
| Registry record updated | August 11, 2026 |
| Trial ID | NCT05237141 on ClinicalTrials.gov |
Is this trial a fit for you?
✓Likely a good fit
Ideal candidates are women with regular menstrual cycles who are not currently pregnant and wish to use the etonogestrel implant for contraception.
✕Probably not a fit
Patients with known hypersensitivity to etonogestrel or those with medical conditions affecting liver function may not benefit from this study.
A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.
What this trial studies
This study evaluates the effectiveness of the etonogestrel implant as a method of emergency contraception by inserting it before the luteinizing hormone (LH) surge. It is a single-site, open-label pilot study that will assess ovulation rates through serum hormone levels and transvaginal ultrasound after the implant is placed. The hypothesis is that the implant can inhibit ovulation if inserted prior to the LH surge, leveraging the rapid hormonal changes associated with the implant. Participants will be women with regular menstrual cycles who desire the implant for contraception.
Why it matters
Potential benefit: If successful, this approach could provide a new method of emergency contraception that is effective and timely.
How similar studies have gone: This study is novel as there have been no prior studies specifically evaluating the etonogestrel implant for emergency contraception in this manner.
Who can join: the full rules
Show full inclusion / exclusion criteria
Inclusion Criteria: * BMI less than or equal to 28kg/m2 * Intact uterus with at least one ovary * Regular menstrual cycles that occur every 21-35 days * If patient is postpartum or post-second trimester abortion, 3 menses (2 cycles) must have occurred prior to enrollment * If patient had a first trimester abortion or pregnancy loss, she must have one spontaneous menses prior to enrollment * Desires insertion of an etonogestrel contraceptive implant for contraception * Not currently pregnant or trying to become pregnant * Willing to abstain from medications and supplements known to induce/inhibit CYP3A4 during the study Exclusion Criteria: * Have a known hypersensitivity or contraindications to etonogestrel. * Medical conditions that affect liver function (e.g., hepatitis, cirrhosis; assessed via participant self-report) * Known or suspected current alcohol dependence syndrome or any illicit drug use that may affect the metabolism of the etonogestrel. * Uncontrolled thyroid disorder. * Use of long-acting injectable hormonal contraceptive within the past 9 months * Current use of hormonal oral, patch, intravaginal, or intrauterine contraception
Where it's running
-
University of Colorado Denver
Aurora, Colorado, United States Recruiting
Study contacts
- Study coordinator: Emily Graves, BS
- Email: emily.graves@cuanschutz.edu
- Phone: 303-724-3514
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How to take part
- Review the eligibility criteria above with your treating physician.
- Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
- Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.