Dr. Frances Hayes

Dr. Frances Hayes is the Associate Chief for Clinic and Education of the REU, and Clinic Director of the Reproductive Endocrine Associates practice, as well as the Division Clinical Director for Endocrine. She also holds the role of Director of the Reproductive Endocrine Unit Reference Laboratory, and is an Associate Professor of Medicine at Harvard Medical School. She received her medical degree from University College Dublin, Ireland where she is board certified in internal medicine and endocrinology.

Dr. Hayes’ main clinical and research interest is male hypogonadism a topic on which she has lectured widely. In addition, she sees men and women with a variety of reproductive disorders including infertility, polycystic ovary syndrome and menstrual disorders.Her clinical practice covers the spectrum of reproductive endocrinology including polycystic ovary syndrome, infertility, and male and female hormone replacement therapy for hypogonadism. She coordinates the NIH-sponsored program of long-term pulsatile GnRH administration for men with congenital GnRH deficiency, a therapy that is currently limited to a few academic centers in the United States. In addition, she has expertise in ovulation induction with clomiphene, gonadotropins and pulsatile GnRH for women with idiopathic or anovulatory infertility.

Dr. Hayes’ area of expertise is human reproductive physiology, a topic on which she has published widely. Her research interests include the neuroendocrine regulation of fertility in men, androgen replacement therapy and the relationship between testosterone and insulin resistance in men. She was recently part of a panel of experts convened by the Endocrine Society to provide guidelines for androgen replacement in older men.

To date, her research studies have shown that insulin resistance is associated with a decrease in the secretion of testosterone from the testes in men. She is currently examining the impact of short-term medical castration on insulin sensitivity in normal healthy volunteers as well as the impact of testosterone supplementation in men with the metabolic syndrome. Given the significant cardiovascular morbidity and mortality associated with obesity and type 2 diabetes, a clearer understanding of the interplay between testosterone and insulin resistance has important public health implications and may facilitate the development of new therapies for these very common disorders.


• Hayes FJ, Taylor AE, Martin KM, Hall JE. Use of a GnRH antagonist as a physiologic probe in polycystic ovary syndrome: assessment of neuroendocrine and androgen dynamics. J Clin Endocrinol Metab 1998; 83:2343-2349

• Seminara SB*, Hayes FJ*, Crowley Jr, WF. GnRH deficiency in the human (Idiopathic hypogonadotropic hypogonadism & Kallmann’s syndrome): Pathophysiologic and genetic considerations. Endo Rev 1998;19:521-539

• Hayes FJ, Seminara SB, DeCruz S, Boepple PA, Crowley WF Jr. Aromatase inhibition in the human male reveals a hypothalamic site of estrogen feedback. J Clin Endocrinol Metab. 2000; 85:3027-3035.

• Hayes FJ. Testosterone – Fountain of Youth or Drug of Abuse? J Clin Endocrinol Metab. 2000: 85:3020-3023

• Hayes FJ, DeCruz, Seminara SB, Boepple PA, Crowley WF Jr. Differential regulation of gonadotropin secretion by testosterone in the human male: absence of a negative feedback effect of testosterone on FSH secretion. J Clin Endocrinol Metab. 2001; 86:53-58

• Hayes FJ, Pitteloud N, DeCruz S, Crowley WF Jr, Boepple PA. Importance of Inhibin B in the Regulation of FSH secretion in the human male. J Clin Endocrinol Metab. 2001;86: 5541-5546

• Pitteloud N, Villegas J, Dwyer AA, Crowley WF, Jr, McPhaul MJ, Hayes FJ. Acute stress masking the biochemical phenotype of partial androgen insensitivity syndrome in a patient with a novel mutation in the androgen receptor. J Clin Endocrinol Metab. 2004; 89:1053-1058.

• Pitteloud N, Hardin M, Dwyer AA, Valassi E, Yialamas M, Elahi D, Hayes FJ. Increasing insulin resistance is associated with a decrease in Leydig cell testosterone secretion in men. J Clin Endocrinol Metab. 2005 May;90(5):2636-41. Epub 2005 Feb 15.

• Pitteloud N, Mootha VK, Dwyer AA, Hardin M, Lee H, Eriksson KF, Tripathy D, Yialamas M, Groop L, Elahi D, Hayes FJ. Relationship between testosterone levels, insulin sensitivity, and mitochondrial function in men. Diabetes Care. 2005 Jul;28(7):1636-42. PMID: 15983313 [PubMed – indexed for MEDLINE]

• Bhasin S, Cunningham GR, Hayes FJ, Matsumoto AM, Snyder PJ, Swerdloff RS, Montori VM. Testosterone therapy in adult men with androgen deficiency syndromes: an endocrine society clinical practice guideline. J Clin Endocrinol Metab. 2006 Jun;91(6):1995-2010. Epub 2006 May 23. Erratum in: J Clin Endocrinol Metab. 2006 Jul;91(7):2688. PMID: 16720669