Clinical trial · Interventional
The Role of Estrogen in Luteinizing Hormone Surge and Ovulation
NCT01999569CI-TRIAL-00057991completedPhase 4Results postedClinicalTrials.gov clinicaltrialsProvenance
- Source
- ClinicalTrials.gov
- Retrieved
- Sep 8, 2026
- Layer
- normalized (units and labels harmonized; values unchanged)
- Run
- ING-CLINICALTRIALS-20260908-000001
Summary
Brief summary (as posted)
The purpose of the study is to establish that sustained estrogen levels are the driving force for the LH surge, and are thereby necessary for ovulation to occur. We predict that by reducing levels of circulating estrogen, letrozole, an aromatase inhibitor, will inhibit ovulation from occurring.
Conditions
Conditions (2)
Free-text conditions as registered, with the CancerIndex entity they were reconciled to and the match type.
| Condition (as posted) | Mapped entity | Match | Confidence |
|---|---|---|---|
| Ovarian Cysts | — | UNRESOLVED | — |
| Ovulation Disorder | — | UNRESOLVED | — |
Interventions
Interventions (1)
| Intervention | Type | Mapped drug | Match |
|---|---|---|---|
| Letrozole | Drug | Letrozole | ALIAS |
Design
Arms and outcomes
Arms (2)
- type
- NO_INTERVENTION
- label
- Control
- description
- Control cycle. No intervention.
- type
- EXPERIMENTAL
- label
- Letrozole
- description
- 5mg daily
- interventionNames
- Drug: Letrozole
Primary outcomes (1)
- measure
- Number of Participants With Progesterone Level Greater Than 1.5 ng/mL
- timeFrame
- Cycle days 12-22
- description
- Serum progesterone ng/mL drawn during cycle days twelve through 22
Secondary outcomes (2)
Eligibility
Eligibility (as posted)
- Sex
- Female
- Minimum age
- 18 Years
- Maximum age
- 40 Years
Show eligibility criteria text
Inclusion Criteria: * Patient having regular menstrual cycles between 26-30 days * Ages 18-40 * Patient must not be sexually active during the study period, or if so must be using a reliable form of non-hormonal birth control including tubal ligation or vasectomy, non-hormonal intrauterine contraceptive device (IUD), or condoms with spermicide. * Willing to participate in study and available for all monitoring visits. * IRB consent Exclusion Criteria: * Patient must NOT have used hormonal contraception three months or less prior to study. * Irregular menstrual cycles (\<26 days or \>30 days within the last 6 months. * Untreated thyroid dysfunction or hyperprolactinemia * Pregnancy (current or within 3 months) or breastfeeding * Allergy or contraindication to letrozole
References
Publications (7)
- BACKGROUNDChristensen A, Bentley GE, Cabrera R, Ortega HH, Perfito N, Wu TJ, Micevych P. Hormonal regulation of female reproduction. Horm Metab Res. 2012 Jul;44(8):587-91. doi: 10.1055/s-0032-1306301. Epub 2012 Mar 21. PMID 22438212
- BACKGROUNDMorioka N, Zhu C, Brannstrom M, Woessner JF, LeMaire WJ. Mechanism of mammalian ovulation. Prog Clin Biol Res. 1989;294:65-85. PMID 2657783
- BACKGROUNDGoh HH, Ratnam SS. The LH surge in humans: its mechanism and sex difference. Gynecol Endocrinol. 1988 Jun;2(2):165-82. doi: 10.3109/09513598809023624. PMID 3055821
- BACKGROUNDLaven JS, Fauser BC. What role of estrogens in ovarian stimulation. Maturitas. 2006 Jul 20;54(4):356-62. doi: 10.1016/j.maturitas.2006.04.022. Epub 2006 Jun 19. PMID 16782289
- BACKGROUNDCasper RF, Mitwally MF. Review: aromatase inhibitors for ovulation induction. J Clin Endocrinol Metab. 2006 Mar;91(3):760-71. doi: 10.1210/jc.2005-1923. Epub 2005 Dec 29. PMID 16384846
- BACKGROUNDMitwally MF, Casper RF. Aromatase inhibition reduces the dose of gonadotropin required for controlled ovarian hyperstimulation. J Soc Gynecol Investig. 2004 Sep;11(6):406-15. doi: 10.1016/j.jsgi.2004.03.006. PMID 15350255
- BACKGROUNDBurstein HJ, Griggs JJ, Prestrud AA, Temin S. American society of clinical oncology clinical practice guideline update on adjuvant endocrine therapy for women with hormone receptor-positive breast cancer. J Oncol Pract. 2010 Sep;6(5):243-6. doi: 10.1200/JOP.000082. Epub 2010 Aug 6. PMID 21197188