OBJECTIVE: Growth hormone (GH) activity might be implicated in male reproductive function. One previous study has suggested significantly reduced semen quality in untreated acromegalic patients due to both reduced sperm counts and sperm motility.

DESIGN AND METHODS: A retrospective study comprising ten uncontrolled hypogonadal acromegalic patients (median age 29 years) who delivered semen for cryopreservation before initiation of testosterone therapy. Semen variables and hormone concentrations were compared to those of ten non-acromegalic hypogonadal men with pituitary disease (age 31 years) and those of young healthy men.

RESULTS: Acromegalic patients vs. non-acromegalic patients had a higher percentage of progressive motile spermatozoa (62 vs. 47%, p = 0.04). Eight of ten acromegalic patients and 82% of controls had total sperm counts above 39 million and progressive motile spermatozoa above 32% (p = 0.55), corresponding to the WHO 2010 reference levels for expected normal fertility for these variables. Non-acromegalic patients vs. healthy controls had reduced percentage of progressive motile spermatozoa (47 vs. 57%, p = 0.02) and only five of ten patients had semen quality above the WHO reference level, which was significantly lower than observed in healthy controls (p = 0.022). Total sperm counts were similar between both patient groups and controls. There were no differences in reproductive hormone levels between acromegalic patients vs. non-acromegalic patients (p-values between 0.10 and 0.61). Compared to healthy controls both patient groups had severely reduced serum testosterone, calculated free testosterone.

CONCLUSIONS: Despite severe hypoandrogenism acromegalic patients had semen quality similar to healthy controls based on determination of the number of progressively motile spermatozoa. By contrast non-acromegalic pituitary patients had reduced sperm motility. Our data do not support reduced semen quality in acromegaly.