Dwyer AA, et al. - In this retrospective study, researchers examined functional hypogonadotropic hypogonadism (FHH) and the neuroendocrine mechanisms, genetics and natural history underlying it. Participants in the study were healthy post-pubertal men presenting with symptoms of hypogonadism in the context of excessive exercise (>10 hours/week) or weight loss (>10% of bodyweight). Investigators found that patients had significantly lower BMI, testosterone, luteinizing hormone (LH) and mean LH pulse amplitudes, but normal LH pulse frequency, serum FSH and sperm counts. LH pulse patterns are comparable in male FHH and hypothalamic amenorrhea females.