1. Reversal and relapse of hypogonadotropic hypogonadism: resilience and fragility of the reproductive neuroendocrine system.

    Journal of Clinical Endocrinology & Metabolism 99(3):861 (2014) PMID 24423288 PMCID PMC3942233

    A subset of patients diagnosed with idiopathic hypogonadotropic hypogonadism (IHH) later achieves activation of their hypothalamic-pituitary-gonadal axis with normalization of steroidogenesis and/or gametogenesis, a phenomenon termed reversal. The objective of this study was to determine the nat...
  2. Trial of recombinant follicle-stimulating hormone pretreatment for GnRH-induced fertility in patients with congenital hypogonadotropic hypogonadism.

    Journal of Clinical Endocrinology & Metabolism 98(11):E1790 (2013) PMID 24037890 PMCID PMC3816270

    The optimal strategy for inducing fertility in men with congenital hypogonadotropic hypogonadism (CHH) is equivocal. Albeit a biologically plausible approach, pretreatment with recombinant FSH (rFSH) before GnRH/human chorionic gonadotropin administration has not been sufficiently assessed. The ...
  3. Metabolic effects of Roux-en-Y gastric bypass in obese adolescents and young adults.

    Journal of Pediatric Gastroenterology and Nutri... 56(5):528 (2013) PMID 23274343 PMCID PMC3637417

    Weight loss surgery is an increasingly common treatment option for obese adolescents, but data are limited regarding the metabolic effects of surgical weight loss procedures. We performed a retrospective review of the electronic medical record to determine metabolic outcomes for 24 adolescents a...
  4. A genetic basis for functional hypothalamic amenorrhea.

    New England Journal of Medicine 364(3):215 (2011) PMID 21247312 PMCID PMC3045842

    Functional hypothalamic amenorrhea is a reversible form of gonadotropin-releasing hormone (GnRH) deficiency commonly triggered by stressors such as excessive exercise, nutritional deficits, or psychological distress. Women vary in their susceptibility to inhibition of the reproductive axis by su...
  5. Rathke's cleft cysts in children and adolescents: association with female puberty.

    Journal of Pediatric Endocrinology and Metabolism 23(11):1175 (2010) PMID 21284332

    There are few pediatric data regarding manifestations and outcomes of Rathke's cleft cysts (RCC). We retrospectively reviewed 13 cases treated at Massachusetts General Hospital over 10 years. Age at presentation was 12-17 years, except for one 7-year-old who presented with sexual precocity. Ther...
  6. Adolescent obesity and bariatric surgery.

    Current Opinion in Endocrinology Diabetes and O... 16(1):37 (2009) PMID 19104236

    Examines the effects of bariatric surgery on adolescent obesity. The risks and outcomes of bariatric surgery in adolescence are presently being defined and may be somewhat different from those in adults. Adolescents may have a greater risk of weight regain, and greater risk of noncompliance to t...
  7. Role of seminiferous tubular development in determining the FSH versus LH responsiveness to GnRH in early sexual maturation.

    Neuroendocrinology 90(3):260 (2009) PMID 19829004 PMCID PMC2826435

    The onset of sexual maturation at puberty is a unique developmental period from a neuroendocrine perspective in that it is characterized by enhanced FSH secretion and FSH responsiveness to exogenous GnRH (vs. LH) from the gonadotrope, yet the mechanism of these dynamics remains unclear. This stu...
  8. The relative role of gonadal sex steroids and gonadotropin-releasing hormone pulse frequency in the regulation of follicle-stimulating hormone secretion in men.

    Journal of Clinical Endocrinology & Metabolism 93(7):2686 (2008) PMID 18445673 PMCID PMC2453056

    Our objective was to determine the importance of testosterone (T), estradiol (E(2)), and GnRH pulse frequency to FSH regulation in men. This was a prospective study with four arms. The study was performed at the General Clinical Research Center. There were 20 normal (NL) men and 15 men with idio...
  9. Relative roles of inhibin B and sex steroids in the negative feedback regulation of follicle-stimulating hormone in men across the full spectrum of seminiferous epithelium function.

    Journal of Clinical Endocrinology & Metabolism 93(5):1809 (2008) PMID 18270253 PMCID PMC2386680

    Our aim was to explore the relative roles of gonadal sex steroids and inhibin B in the regulation of FSH across a spectrum of seminiferous epithelium function. The study included three groups: group I, healthy men (n = 31); group II, men with idiopathic hypogonadotropic hypogonadism receiving pu...
  10. Inhibition of luteinizing hormone secretion by testosterone in men requires aromatization for its pituitary but not its hypothalamic effects: evidence from the tandem study of normal and gonadotropin-releasing hormone-deficient men.

    Journal of Clinical Endocrinology & Metabolism 93(3):784 (2008) PMID 18073301 PMCID PMC2266963

    Studies on the regulation of LH secretion by sex steroids in men are conflicting. Our aims were to determine the relative contributions of testosterone (T) and estradiol (E2) to LH regulation and localize their sites of negative feedback. This was a prospective study with three arms. The study w...
  11. Interplay between dose and frequency of GnRH administration in determining pituitary gonadotropin responsiveness.

    Neuroendocrinology 87(3):142 (2008) PMID 18063854

    The dose, frequency and contour of GnRH stimulation of the pituitary gonadotrope have been shown to be independent variables influencing pituitary LH secretion. The dynamic interaction between these variables during physiological and pathophysiological states has yet to be examined. Twelve men w...
  12. Predictors of outcome of long-term GnRH therapy in men with idiopathic hypogonadotropic hypogonadism.

    Journal of Clinical Endocrinology & Metabolism 87(9):4128 (2002) PMID 12213860

    GnRH treatment is successful in inducing virilization and spermatogenesis in men with idiopathic hypogonadotropic hypogonadism (IHH). However, a small subset of IHH men, poorly characterized to date, fail to reach a normal testicular volume (TV) and produce sperm on this therapy. To determine pr...
  13. The role of prior pubertal development, biochemical markers of testicular maturation, and genetics in elucidating the phenotypic heterogeneity of idiopathic hypogonadotropic hypogonadism.

    Journal of Clinical Endocrinology & Metabolism 87(1):152 (2002) PMID 11788640

    As our knowledge of the molecular mechanisms underlying idiopathic hypogonadotropic hypogonadism (IHH) expands, it becomes increasingly important to define the phenotypic spectrum of IHH. In this study we examined historical, clinical, biochemical, histological, and genetic features in 78 men wi...