The Role of Estrogen in Luteinizing Hormone Surge and Ovulation

Summary

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.

Timeline

Start

2007-04

Primary completion

2008-05

Completion

2008-05

Publications

• Background Christensen 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.
• Background Morioka N, Zhu C, Brannstrom M, Woessner JF, LeMaire WJ. Mechanism of mammalian ovulation. Prog Clin Biol Res. 1989;294:65-85.
• Background Goh 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.
• Background Laven 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.
• Background Casper 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.
• Background Mitwally 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.
• Background Burstein 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.

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