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Investigating the Regulation of Reproductive Hormones in Adult Men

This study has been completed.
Information provided by:
Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) Identifier:
First received: October 25, 2006
Last updated: February 12, 2015
Last verified: April 2010

The purpose of the research study is to learn more about the regulation of reproductive hormones in adult men. We would like to understand what role testosterone and estradiol play in controlling the release of LH (lutenizing hormone) and FSH (follicle stimulating hormone). Testosterone and estradiol come from the testes, and LH and FSH are released from a gland in the head called the pituitary.

Men involved in the study will have detailed evaluations that involve overnight stays in the hospital and frequent blood sampling. The men in the study will also be receiving medications that affect the levels of various hormones in the body. This will allow the researchers to learn how various hormones influence each other. Men that participate in the study will receive medical evaluations and monetary compensation. Information gathered from this study will help in the development of new treatments for infertility and potentially new hormonal forms of contraception.

Condition Intervention
Kallmann Syndrome Hypogonadism Gonadal Disorder Drug: ketoconazole Drug: gonadotropin releasing hormone (GnRH)

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)
Primary Purpose: Health Services Research
Official Title: Feedback Control of FSH Secretion in the Human Male

Resource links provided by NLM:

Further study details as provided by Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD):

Primary Outcome Measures:
  • serum hormone levels [ Time Frame: Baseline, Day 3, and Day 6 ]

Estimated Enrollment: 175
Study Start Date: July 1995
Study Completion Date: February 2007
Primary Completion Date: February 2007 (Final data collection date for primary outcome measure)
Intervention Details:
    Drug: ketoconazole
    loading dose of 1g followed by a maintenance dose of 400 mg PO QID for 7 days
    Drug: gonadotropin releasing hormone (GnRH)
    Pulsatile GnRH (25 ng/kg per bolus every two hours via microinfusion pump titrated to reach normal serum testosterone levels)
Detailed Description:
In the United States 10-15% couples seek evaluation for infertility, of whom a male factor is identified in approximately 50% of cases. To date, however, most infertility research has focused on the female partner and in the majority of instances the etiology of male infertility remains poorly understood with inconsistent elevation in FSH levels. Given that spermatogenesis is highly dependent on FSH secretion, this project will focus on delineating the feedback control of FSH in the human male. Such studies, although difficult to perform in the human, are critical to understanding not only the pathophysiology of male infertility, but also to determining the feasibility of hormonal approaches to male contraception. In this protocol, studies of normal, GnRH-deficient and agonadal men employing reversible sex steroid ablation, physiologic sex steroid replacement and manipulation of the GnRH input to the pituitary will permit the non-steroidal, sex steroid, and GnRH-dependent components of FSH regulation to be selectively elucidated.

Ages Eligible for Study:   18 Years to 50 Years   (Adult)
Sexes Eligible for Study:   Male
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • Men aged 18 to 50 years
  • In good health
  • On no medications

Exclusion Criteria:

Subjects will not be enrolled in this study if there is a history of:

  • Liver disease or if screening blood tests demonstrate abnormal liver function tests
  • Excessive alcohol consumption
  • Illicit drug use
  • Severe drug allergy
  • Use of any concomitant medications
  • Peptic ulcer disease or gastritis
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT00392457

United States, Massachusetts
Massachusetts General Hospital
Boston, Massachusetts, United States, 02114-2696
Sponsors and Collaborators
Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)
Principal Investigator: William F Crowley, Jr., MD Massachusetts General Hospital
  More Information

Additional Information:

Responsible Party: William F. Crowley Jr., MD, MGH Identifier: NCT00392457     History of Changes
Other Study ID Numbers: R01 HD15788 - 234
Study First Received: October 25, 2006
Last Updated: February 12, 2015

Keywords provided by Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD):
Idiopathic Hypogonadotropic Hypogonadism
Kallmann Syndrome

Additional relevant MeSH terms:
Kallmann Syndrome
Gonadal Disorders
Endocrine System Diseases
46, XY Disorders of Sex Development
Disorders of Sex Development
Urogenital Abnormalities
Congenital Abnormalities
Genetic Diseases, Inborn
Hormones, Hormone Substitutes, and Hormone Antagonists
Physiological Effects of Drugs
Antifungal Agents
Anti-Infective Agents
14-alpha Demethylase Inhibitors
Cytochrome P-450 Enzyme Inhibitors
Enzyme Inhibitors
Molecular Mechanisms of Pharmacological Action
Steroid Synthesis Inhibitors
Hormone Antagonists
Cytochrome P-450 CYP3A Inhibitors processed this record on September 21, 2017