Re-determination of upper reference range of follicular stimulating hormone in infertile men

FSH in infertile patients may be measured in the normal range and abnormal semen analysis findings may be observed in patients with normal FSH values. A recent study predicts that the sperm morphology and concentration may be impaired if the FSH value is above 4.5 IU/L. Therefore, this study aimed to define a clinically more useful upper limit for FSH as an indicator for male infertility. In this study 1,893 infertile male patients were evaluated retrospectively. Physical examination, hormone analysis (total testosterone (TT), FSH, luteinizing hormone (LH), estradiol (E2), sex hormone binding globulin (SHBG) and prolactin (PRL)), semen analyzes were recorded and analyzed retrospectively. Logistic regression analysis, 95% confidence intervals and probability ratios were calculated to show the relationship between categorical hormone levels (quarters) and semen parameters. Hormone levels were categorized using the distribution quarters in the study population. FSH values of 62% of the cases with sperm concentration <15 million/ml were greater than 4.8 IU/L. 59.7% of patients with sperm count <39 million had FSH values greater than 4.8 IU/L. In conclusion, FSH values above 4.8 IU/L were found to be abnormal when the male factor was investigated for infertility.

FSH: Follicular Stimulating Hormone; GnRH: Gonadotropin-releasing Hormone; HPGA: Hypothalamic-Pituitary-Gonadal Axis; TT: Total Testosterone; LH: Luteinizing Hormone; E2: Estradiol; SHBG: Sex Hormone Binding Globulin; PRL: Prolactin; WHO: World Health Organization; AUC: Area Under the Curve.