Objectives/hypothesis: Males with isolated hypogonadotropic hypogonadism (IHH) fail to undergo normal sexual development, including the lack of masculinization of the larynx. The objective of this study was to measure the mean vocal fundamental frequency (MF0) in IHH patients and determine the impact of androgen treatment. An additional aim was to compare the MF0 between IHH patients and controls.
Study design: Prospective observational study.
Methods: Twenty-four patients with IHH were identified along with 30 normal males and females. Voice recordings were obtained on all subjects. Androgen therapy was administered to the IHH patients. The MF0 and serum sex hormone levels were measured before treatment and at intervals during therapy. These results were compared with the pretreatment data within the IHH group. Voice parameters were also compared between the pre- and posttreatment IHH patients and the normal males and females.
Results: The MF0 in untreated IHH patients was 229 +/- 41 Hz. This was intermediate between the normal male (150 +/- 22 Hz, P < .001) and normal female patients (256 +/- 29 Hz, P < .01). After treatment, the MF0 in the IHH group decreased to 173 +/- 30 Hz (P < .0001); indeed, their posttreatment MF0 approached that of normal males (P < .08). Serum hormone levels responded to the injected testosterone, but these levels did not directly correlate with MF0.
Conclusions: MF0 in IHH patients is intermediate between normal male and female levels. After treatment with testosterone, these values approach the range of normal males. This prospective study details the impact of androgens on the larynx and vocal function in patients with IHH.