Total Motile Sperm Count in Adolescent Boys with Varicocele is Associated with Hormone Levels and Total Testicular Volume.

Purpose: The risk factors for future infertility in adolescents with varicocele are controversial, and little is known about the association between hormone levels and semen parameters. Semen analysis is likely the closest marker of fertility but may be difficult to obtain in some boys secondary to personal, familial or religious reasons. Identifying other clinical surrogates for abnormal semen parameters may offer an alternative for assessing varicocele severity in these boys. We hypothesized that hormone levels and total testicular volume are predictive of abnormal total motile sperm count.

Materials And Methods: We retrospectively reviewed Tanner 5 boys with palpable left varicoceles who underwent a semen analysis and had serum hormone levels tested (luteinizing hormone, follicle-stimulating hormone, inhibin B, anti-müllerian hormone and/or total testosterone) within a 6-month period. Total testicular volume was also calculated. Abnormal total motile sperm count was defined as <9 million sperm per ejaculate.

Results: A total of 78 boys (median age 17.2 years, IQR 16.5-18.0) were included. Luteinizing hormone, anti-müllerian hormone and total testosterone were not correlated with any semen analysis parameter. There was a negative correlation between follicle-stimulating hormone and total motile sperm count (ρ -0.35, p=0.004) and positive correlation between inhibin B and total motile sperm count (ρ 0.50, p <0.001). Total testicular volume was significantly positively correlated with total motile sperm count (ρ 0.35, p=0.01). ROC analyses revealed an optimal follicle-stimulating hormone cutoff of 2.9, an optimal inhibin B cutoff of 204 and an optimal total testicular volume cutoff of 34.4 cc to predict abnormal total motile sperm count.

Conclusions: Total motile sperm count is inversely associated with follicle-stimulating hormone levels, and directly associated with inhibin B levels and total testicular volume. Optimized cutoffs for serum follicle-stimulating hormone, inhibin B and total testicular volume may prove to be reasonable surrogates for total motile sperm count in boys who defer semen analysis for personal or religious/cultural reasons.