EFFECTS OF PURE HUMAN FOLLICLE-STIMULATING-HORMONE (PFSH) ON SPERM QUALITY CORRELATE WITH THE HYPOPHYSEAL RESPONSE TO GONADOTROPIN-RELEASING-HORMONE (GNRH)

In 41 men with idiopathic infertility, the effect of pure follicle-sti mulating hormone (pFSH) therapy on semen parameters was evaluated in r elation to the results of the gonadotrophin-releasing hormone (GnRH) s timulation test in an open study. The patients showed a mean (+/-stand ard error) sperm concentration of 15.84 (+/-2.87) Mill. ml(-1), 41.02 (+/-4.19)% of the spermatozoa were motile and 46.16 (+/-2.36)% normomo rph before treatment. All patients were administered 150 IU pFSH subcu taneously three times weekly for 10 weeks. After therapy with pFSH, no significant differences compared with the pre-treatment sperm charact eristics were observed (P>0.05) except for the velocity average path, VAP (P=0.029). However, the stimulation factors of FSH in the GnRH tes t showed a significantly negative correlation with the pFSH mediated i mprovement of sperm concentration (r=-0.662, P=0.000002), of percentag e of normomorph spermatozoa (r=-0.480, P=0.0015) and total count of mo tile spermatozoa per ejaculate (r=-0.567, P=0.00014). In consequence, the patients were divided into two groups depending on the stimulation factor of hypophyseal FSH secretion, FSH-SF. The cut-off point of the FSH-SF was set at 1.7 because the correlation analyses detected a 1.5 -fold improvement of sperm parameters at this hypophyseal response on average. Pure FSH treatment increased the concentration of spermatozoa (P=0.0007), the total count of motile spermatozoa in the ejaculate (P =0.015) as well as the computer-aided sperm motion parameters VAP (P=0 .029) and velocity curve linear, VCL (P=0.049) in patients with FSH-SF <1.7, whereas in the patient group with FSH-SF>1.7 no improvement of s emen parameters was found. Insufficient stimulation of hypophyseal FSH secretion may be a prerequisite but not a guarantee for responsivenes s to pFSH treatment. The results of the present investigation suggest that FSH stimulation in the GnRH test should be taken into account in idiopathic infertile men before pFSH therapy.